Recent Homework Questions About Substance Abuse
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life orientation
provide recommendations on how to address substance abuse
Tuesday, May 21, 2013 at 12:27pm
TEACHER AIDE,CHILDREN, FAMILIES, SOCIETE
1. Larry is a very aggressive four-year-old child. He watches many television programs that contain violence. Its most likely that A. he will become overactive. C. his behavior wont change. B. he will become depressed. D. his behavior will become more aggressive. 2...
Saturday, May 18, 2013 at 5:00pm
life orientation
in 10-15 lines critically discuss 5 ways in which substance abuse impacts on the community.
Tuesday, May 14, 2013 at 9:55am
life orientation
describe the substance abuse of both legal and illegal drogs among the youth and explain the the factors that contribute to the disease.
Monday, May 13, 2013 at 9:24am
Chemistry
If I used 100% larger sample mass of an unknown substance what effect would that have on the empirical formula that would be obtained?
Monday, May 13, 2013 at 2:20am
science
A form of energy that is always transferred from a warmer substance to a cooler one.
Sunday, May 12, 2013 at 9:04pm
Algebra 2
A 14 gram sample of a substance that's used to preserve fruit and vegetables has a k-value of 0.1092. Find the substance's half-life, in days. Round your answer to the nearest tenth.
Tuesday, May 7, 2013 at 2:11pm
Science
Please check my answers (at the bottom) with these questions. 1. An apple quickly changes color when exposed to air. This demonstrates a ________. (1 point) physical property chemical property physical change all of the above 2. When a chunk of dry ice is at room temperature, ...
Tuesday, May 7, 2013 at 12:22pm
Chemistry
A substance releases 496kJ of heat as 2.60 moles condense from a gas into a liquid. What is the molar heat of vaporization of the substance?
Tuesday, May 7, 2013 at 12:14pm
Pre-Algebra
Tempurature of substance increases by 10°C in 5 minutes. Write it as a unit rate. Then convert it to degrees Fahrenheit per hour.
Monday, May 6, 2013 at 7:46pm
life orientation
In 10-15 lines critically discuss 5 ways in which the human or environmental problem impact on the community in related to substance abuse
Monday, May 6, 2013 at 6:00pm
substance
10-15 lines critically discuss 5 ways in which the human problem impacts on the community
Friday, May 3, 2013 at 2:52am
PHYSICS!
The quantity of heat that changes the temperature of a mass of a substance is given by , where is the specific heat capacity of the substance. For example, for , . And for a change of phase, the quantity of heat that changes the phase of a mass is , where is the heat of fusion...
Thursday, May 2, 2013 at 2:25pm
Life orientation
Recommendations on how to address substance abuse
Thursday, May 2, 2013 at 12:15pm
Life orientation
Five ways in wich substance abuse problem impact on the communities
Thursday, May 2, 2013 at 12:10pm
Chemistry
I just to know how to identify the substance that is reduced, the substance that is oxidized, the oxidizing agent and the reducing agent in each reaction. As (s) + ClO3-(aq) → H3AsO3 (aq) + HClO(aq) CN-(aq) + MnO4-(aq) → CNO-(aq) + MnO2(s) C2H5OH + MnO4- → ...
Tuesday, April 30, 2013 at 11:01pm
chemistry: please check answers.
1. How many valence electrons does a carbon atom have? A) 1 B) 2 C) 3 D) 4<<my answer 2. How many double covalent bonds are in an alkane? A) 0<<my answer B) 1 C) 2 D) 3 3. What is the general formula for a straight-chain alkane? A) CnHn B) CnHn+2 C) CnH2n D) CnH2n+...
Tuesday, April 30, 2013 at 10:30am
chemistry
Pipette 3 drops of oil into a test tube of water and shake. Describe what takes place and why? - Would it be the oil settles at the top of the water, because the oil is less dense, and its a non-polar substance, so it doesn't mix with a polar substance (water). Add 1 scoop...
Tuesday, April 30, 2013 at 12:28am
Physics
A bullet is made up of what substance?
Monday, April 29, 2013 at 5:52am
Physics
A bullet is made up of what substance?
Monday, April 29, 2013 at 5:51am
Physics
A bullet is made up of what substance?
Monday, April 29, 2013 at 5:51am
Physics
A bullet is made up of what substance?
Monday, April 29, 2013 at 5:20am
algebra
Andrew measures they amount of a very unstable substance to be 100 moles. the half life of this substance is 3 days(after 3 days, half is gone). write an exponential function that models this situation where Y is the amount of substance and X is time in days. use your equation...
Friday, April 26, 2013 at 11:11pm
Science
During an experiment, you find that you can dissolve 3.6 g of a substance in 300 mL of water at 25°C. How much of the substance would you predict that you could dissolve in 600 mL of water at the same temperature? Can somebody help me with this? I don't get it.
Thursday, April 25, 2013 at 11:26am
Life orientation
Describe the life style disease/behaviour and explain 5 or more factors that contribute to the disease of substance abuse of both legal and illegal drugs among the youth
Thursday, April 25, 2013 at 10:00am
physics
Objects A and B have the same mass of 3.4 kg and are at their melting points. They melt when 4.9 × 104 J of heat is added to A and when 11 × 104 J is added to B. (a), (b) Determine the latent heat of fusion for the substance from which each object is made. (c) Find...
Wednesday, April 24, 2013 at 1:25pm
life orientation
Substance abuse of both legal and illegal drugs among the youth
Tuesday, April 23, 2013 at 3:13am
Life Orientation
Explain 5(or more)factors that contribute to the substance abuse of both Legal and Illegal drugs among the youth
Sunday, April 21, 2013 at 11:10am
sew
A chemical substance that causes dyes to set is called?
Sunday, April 21, 2013 at 10:40am
ELECTROLYSIS OF ZnI2
ELECTROLYSIS OF ZnI2 if you have done this experiment Please help me answer these questions as i missed the last half of my chem lab today. 1. What color change occurred when the wire is first heated. -next question is... What is the identity of the liberated metal? 2. what ...
Thursday, April 18, 2013 at 7:09pm
chemistry
What is the specific heat of an unknown substance if a 2.53 g sample releases 13.1 cal as its temperature changes from 25.5°C to 21.3°C?
Wednesday, April 17, 2013 at 4:08pm
Grd 12 life orientation
Describe the life style behaviour and explain 5 factors that contribute to the substance abuse of both legal and illegal drugs among the youth
Wednesday, April 17, 2013 at 2:39pm
life orientation
in 15 lines critically discuss 5 ways in which the human or environmental problem impacts on the community in substance abuse
Wednesday, April 17, 2013 at 11:09am
chemistry
What is the specific heat of an unknown substance if a 2.31 g sample releases 12.5 cal as its temperature changes from 24.9°C to 20.7°C? Please explain ans show steps.
Tuesday, April 16, 2013 at 7:26pm
Chemistry
Substance X (MW=356gm) is a weak acid. Its Ka is 1.7x10^-3. Calculate pH of725ml of the following solutions: a)Containing 0.187 mol of substance x b)containing 127gm of Substance x I have been trying to figure this problem out for hours now and do not get it. Please help me ...
Tuesday, April 16, 2013 at 11:54am
science
Why is it difficult to distinguish between some pure substances and solutions? What methods can overcome this to define if either it is a pure substance or solution?
Sunday, April 14, 2013 at 10:56pm
Chemistry
how to find the mass of the substance if the only given is the molar mass???
Sunday, April 14, 2013 at 1:11pm
Life orientation
Which institution or organisation involved in supporting or giving redress to substance abuse?
Sunday, April 14, 2013 at 9:52am
AP CHEM HELP
When NH3 is added to solid Hg2Cl2, some of the mercury ions are oxidized and some are reduced. A reaction where the same substance is both oxidized and reduced is called a disproportionation reaction. Write equations for each of these half-reactions. HELP
Tuesday, April 9, 2013 at 7:03pm
science
1. _____ is the process by which food is broken down so that nutrients can be used by the body. (1 point) Absorption Digestion Elimination Ingestion 2. What type of digestion takes place in the mouth? (1 point) chemical mechanical chemical and mechanical neither chemical nor ...
Monday, April 8, 2013 at 7:51pm
Chemistry
H2C2O4.2H2O(s) is primary standard substance. 2.3688g of oxalic acid hydrate were completely neutralized by 42.56ml of NaOH solution. Calculate the molar concentration of the NaOH solution. Write the balanced equation for the reaction.
Monday, April 1, 2013 at 8:08pm
Grade 12 Life orientation
Critically discuss 5 ways in which lifestyle/behaviour substance of both legal and illegal drugs impact on the teenagers?
Saturday, March 30, 2013 at 12:26pm
7th Grade Sience
1. A person's belief that he or she needs a drug to feel good or function normally (1 point) addiction psychological dependence emphysema tolerance 2. A large, dome-shaped muscle below the lungs (1 point) trachea alveoli diaphragm emphysema 3. Smoke that is inhaled and ...
Thursday, March 28, 2013 at 2:46pm
science
Monique heated the black substance with some corbon. Copper was formed. what are all the elements in the blue crystals ?
Tuesday, March 26, 2013 at 5:56am
Biology
Eutrophication refers to 1. the concentration of a toxic substance in the tissues of organisms. 2. depletion of mineral resources as a result of leaching. 3. the warming of the earths surface. 4. the damage to the ozone layer that protects the earth from UV light. 5. ...
Tuesday, March 19, 2013 at 6:24pm
calculus
assume that during the first 3 minutes after a foreign substance is introduced into the blood,the rate R'(t) at which new antibodies are produced(in thousands of antibodies per minute) is given by R'(t)=t/(t^2+1) where t is in minutes.find the total quantity of new ...
Tuesday, March 19, 2013 at 3:06am
science
A substance is added to the solution of Barium sulphate,yellow precipitate is formed.What is that substance?
Wednesday, March 13, 2013 at 4:57am
chemistry
Plastic articles can be chromium-plated by coating them with thin layer of graphite paste,placing them in a bath of aqueous chromium(III) sulphate and electroplating. a)Suggest a reason why the article is first coated with graphite. b)what substance could be used for the other...
Sunday, March 10, 2013 at 6:39am
Chemistry
Recall that all aqueoous solutions contain_____. Water can also undergo ____. This process is called the ______of water. The reaction can be written as: Notice the double arrow in the reaction. This indicates that the reaction is_____. However, only a tiny fraction of water ...
Thursday, March 7, 2013 at 9:53pm
Chemistry
These blanks I REALLLY need your help. Our teacher gave the teaching job to this other I think coop student who wants to be a teacher to teach for a day but I| seriously don't understand anything she said..in short I don't have anyyy clue about this. So please help me...
Thursday, March 7, 2013 at 9:08pm
Chemistry
Can someone check my answers please? I had specific trouble with 7, 13, and 27 (I'm pretty sure my other answers are correct; some reassurance would be nice though). And I have a small question about 8. 1. The ΔHf of an element in its standard state is defined to be 0...
Sunday, March 3, 2013 at 6:05pm
science
A substance has a mass of 12.5 grams and a volume of 9.8 ml.Will the object sink or float in water?
Friday, March 1, 2013 at 11:51am
Chemistry
A 1.065-g sample of an unknown substance is dissolved in 30.00 g of benzene; the freezing point of the solution is 4.25 degrees C. The compound is 50.69% C, 4.23% H, and 45.08% O by mass. Info you might need on benzene: Normal Freezing point,degrees C: 5.53 Kf, degrees m^1: 5....
Monday, February 25, 2013 at 2:19am
Chemistry
I need help in solving this problem: A certain substance has a heat of vaporization of 42.46 kJ/mol. At what Kelvin temperature will the vapor pressure be 5.00 times higher than it was at 291 K? I know that I have to use the Clausius-Clapeyron equation, but what would I be ...
Sunday, February 24, 2013 at 3:27pm
chemistry
sometimes,instead of percentage composition, you will have the composition of a mass sample. using the actual mass of the sample, determine the empirical formula for compounds that have the following analyses. b. a 13.07g sample of an unknown substance is composed of 9.48g of ...
Saturday, February 23, 2013 at 7:34pm
chemistry
difference between solution and pure substance
Thursday, February 21, 2013 at 10:47pm
English
This is a chemistry lab report, but I was wondering if someone could edit the grammar and look at the sentence structure, etc. I know it's really long and boring, but even if you just look over a bit of it, I would really appreciate it. And I'm assuming you don't ...
Thursday, February 21, 2013 at 6:16pm
Physics2
"The heat engine uses 1.00x10^-2 mol of a diatomic gas as the working substance. Determine the temperatures at the 3 points." From 1-2, it's an adiabatic process and the constants are (P)(V^(7/5)) or (T)(V^(2/5)). From 2-3, it's an isobaric process with V/T ...
Thursday, February 21, 2013 at 2:09am
gen. chemistry
an unknown solid substance weighs 121g. calculate the specific heat if 425.2 cal raise the temperature of the solid from 24.0 degrees C to 55.7 degrees C.
Wednesday, February 20, 2013 at 4:36pm
Chemistry (DrBob222)
Hi, here's my (almost) 2-paged lab report introduction (hopefully you remember it from yesterday). I went to class today, and actually a lot of my other classmates' introductions were over 2 pages! Now I'm feeling kind of insecure about mine, and I'm not even ...
Tuesday, February 19, 2013 at 5:39pm
science
A 10g sample of radioactive substances is lift to decay for five half-lives. How much of the radioactive substance remains?
Tuesday, February 19, 2013 at 3:51pm
Chemistry
If I have 50 mL of Lead(II) Nitrate, it is possible for me to calculate how many mole is 1 mL of the substance? Thanks
Sunday, February 17, 2013 at 7:19pm
Physics
Calculate the net charge on a substance consisting of a combination of 7.5 multiplied by 1013 protons and 3.5 multiplied by 1013 electrons. Answer in units of C
Sunday, February 17, 2013 at 10:39am
Physics
A certain substance has a dielectric constant of 2.8 and a dielectric strength of 18.0 MV/m. If it is used as the dielectric material in a parallel-plate capacitor, what minimum area should the plates of the capacitor have to obtain a capacitance of 7.00×10-8 F and to ...
Thursday, February 14, 2013 at 9:44pm
science
when a substance is heated energy is released/ absored. in chemisty this is called an
Wednesday, February 13, 2013 at 11:01am
Chemistry
A substance of Ka of 1 x 10^5 would be classified as a ____. A.strong acid B.weak acid C.strong base D.weak base I think it is B...?
Tuesday, February 12, 2013 at 11:02am
Urgent Chem Help
A certain substance has a heat of vaporization of 55.30 kJ/mol. At what Kelvin temperature will the vapor pressure be 3.50 times higher than it was at 361 K?
Sunday, February 10, 2013 at 8:13pm
ap chemistry
A 6.9 gram sample of a gaseous substance occupies 10 L at 63C and 537 torr. What is the density of the gas under these conditions? Answer in units of g/L
Saturday, February 9, 2013 at 7:58pm
CHEMISTRY
How do we determine whether a substance is pure in a chemical formula ?
Wednesday, February 6, 2013 at 7:25pm
7th grade health please help Ms. Sue!
1. Which substance found in tobacco is a drug that speeds up the heartbeat? (1 point) Tar Carbon monoxide Nicotine Emphysema 2. Which substance found in tobacco causes emphysema, a disease of the lungs? (1 point) Tar Carbon monoxide Nicotine Secondhand smoke 3. Which substance...
Wednesday, February 6, 2013 at 6:37pm
Chemistry
Solution of 50g AgNO3 is mixed with 50g NaCl. a) What mass of AgCl will you get? b) which substance is in redundancy?
Wednesday, February 6, 2013 at 3:21pm
Chemistry
A mole of a pure substance contains 6.02x10^23 atoms. Alway true, sometime true or never true? -I was thinking sometime true since a pure substance can be like H2O but H2O have 3 "atoms" (Is this what you call individual part of H2O?). Each "atoms" have 6....
Tuesday, February 5, 2013 at 6:32pm
physics
Calulate the amount of substance in 120g of trioxocarbonate (iv)ion,co2
Sunday, February 3, 2013 at 11:10am
physics
Calulate the amount of substance io 120g of trioxocarbonate (iv)ion,co2
Sunday, February 3, 2013 at 11:10am
chem
The decomposition of sulfuryl chloride (SO2Cl2) is a first-order process. The rate constant for the decomposition at 660 K is 4.5 10-2 s-1. (a) If we begin with an initial SO2Cl2 pressure of 425 torr, what is the pressure of this substance after 74 s? what is the equation to ...
Saturday, February 2, 2013 at 3:46pm
chem
Rank the following species according to the decreasing energy needed to raise the temperature of 10.0g of the substance by 25.0 degrees celsius Rank from most to least energy needed. Rank these in order of the question. copper aluminum cast iron silver water
Friday, February 1, 2013 at 3:23pm
Organic Chemistry
Why is the melting point of a known compound (ex. acetanilide) determined before the melting point of the unknown compound? I think it is to determine if the unknown is a pure substance but I am not sure..I just need to be pointed in the right direction.
Thursday, January 31, 2013 at 6:30pm
physics
90 g of water at 25C mixed with 50g of another substance at 100C result in 45C what is specific heat of that substance
Tuesday, January 29, 2013 at 9:57pm
science
Would you expect a substance to be a solid, liquid, or gas at absolute zero? Explain your answer.
Tuesday, January 29, 2013 at 6:39pm
Science
An unknown substance has a volume of 25 mL. It is placed into a different container and its volume changes to 50 mL. What happened? Is it a change in state?
Tuesday, January 29, 2013 at 6:21pm
finance
describe the difference between the substance and form of financial statements and give an example of each
Tuesday, January 29, 2013 at 4:34pm
Chemistry
The term mole is used in chemistry to define an amount of a substance. For example, a mole of glucose, blood sugar, weighs 180.16 grams. A common concentration unit for solutions is moles of substance per liter of solution. We abbreviate this with the symbol M. For example, 0....
Monday, January 28, 2013 at 9:11am
Calculus
The half life of a certain radioactive substance is 10 years. How long will it take for 18 gms of the substance to decay to 6 gms? A. 6 ln 10 years B. 10 ln 6 years C. 10 (ln 3)/(ln 6) years D. 18 ln 10 years E. 10 (ln 3)/(ln 2) years
Sunday, January 27, 2013 at 4:36pm
chemistry
what is the equillibrium constant of each of the substance in the equillibrium when concentration of ICl was 0.75M 2ICl(g)=I2+Cl2 kc=o.12
Saturday, January 26, 2013 at 1:00am
dress making
1. Which one of the following is the most complete and accurate definition of fiber? A. A stringy substance from plants B. The hair of an animal C. Man-made threads and yarns D. Basic raw material from which fabric is made 2. An example of a natural fiber is A. nylon. B. ...
Friday, January 25, 2013 at 5:09pm
math
assume the substance has a half-life of 11 years and the initial amount is 126 grams.How long will it be until only 15 % remains?
Friday, January 25, 2013 at 11:43am
Math
assume the substance has a half-life of 11 years and the initial amount is 126 grams. How much remains at the end of 8 years?
Friday, January 25, 2013 at 11:23am
Physics
Light is incident from water onto a flat transparent slab of material, at an angle of 48.8° with the normal. The reflected ray and the refracted ray are perpendicular to each other. What is the index of refraction of the transparent substance?
Thursday, January 24, 2013 at 9:49pm
precal
If the half-life of a certain radioactive substance is 2000 years, estimate how many years must elapse before only 35% of the radioactive substance remains?
Tuesday, January 22, 2013 at 10:15pm
English
1. George Bernard Shaw criticized The Importance of Being Earnest for A.)being too long. B.)not being funny. C.)not having real substance. 2. Choose the word below that best completes the sentence: Hes incredibly ___________; he just cant make up his mind about ...
Monday, January 14, 2013 at 2:02pm
chem-answer check please
Compounds like CCl2F2 are known as chlorofluorocarbons, or CFCs. These compounds were once widely used as refrigerants but are now being replaced by compounds that are believed to be less harmful to the environment. The heat of vaporization of CCl2F2 is 289 J/g. What mass of ...
Thursday, January 10, 2013 at 4:41pm
Please CHECK thanks
Please check and tell me what I got wrong and let me know the correct answer for the problem. Thanks. 1. Diarrhea can be caused by a change in diet and different minerals in the water. True (yes) False 2. Fusion produces less radioactivity than fission. True False (yes) 3. ...
Wednesday, January 9, 2013 at 6:31pm
chemistry
Compounds like CCl2F2 are known as chlorofluorocarbons, or CFCs. These compounds were once widely used as refrigerants but are now being replaced by compounds that are believed to be less harmful to the environment. The heat of vaporization of CCl2F2 is 289 J/g. What mass of ...
Wednesday, January 9, 2013 at 5:23pm
Somebody check this plz..and thanks.
Please check and tell me what I got wrong and let me know the correct answer for the problem. Thanks. 1. Diarrhea can be caused by a change in diet and different minerals in the water. True (yes) False 2. Fusion produces less radioactivity than fission. True False (yes) 3. ...
Wednesday, January 9, 2013 at 4:23pm
Will somebody help me please?
1. Diarrhea can be caused by a change in diet and different minerals in the water. True False 2. Fusion produces less radioactivity than fission. True False 3. Wise travelers eat only cooked vegetables in underdeveloped areas. True False 4. The kilogram is the basic unit of ...
Tuesday, January 8, 2013 at 10:37am
I need help..
1. Diarrhea can be caused by a change in diet and different minerals in the water. True False 2. Fusion produces less radioactivity than fission. True False 3. Wise travelers eat only cooked vegetables in underdeveloped areas. True False 4. The kilogram is the basic unit of ...
Monday, January 7, 2013 at 4:48pm
Please guys. Help me out.
1. Diarrhea can be caused by a change in diet and different minerals in the water. True False 2. Fusion produces less radioactivity than fission. True False 3. Wise travelers eat only cooked vegetables in underdeveloped areas. True False 4. The kilogram is the basic unit of ...
Monday, January 7, 2013 at 1:34pm
Science Somebody Help Me Please..I have a deadline
1. Diarrhea can be caused by a change in diet and different minerals in the water. True False 2. Fusion produces less radioactivity than fission. True False 3. Wise travelers eat only cooked vegetables in underdeveloped areas. True False 4. The kilogram is the basic unit of ...
Monday, January 7, 2013 at 1:23pm
physics
the volume of 50g of a substance is 20 cm^2 if the density of water is 1 g cm^-1 will the object floats or sinks in water.???
Sunday, January 6, 2013 at 11:23am
Chemistry
A volume of 10cm^3 of 2M H2SO4 is placed in a volumetric flas of 250cm^3 and filled to the mark with distilled water. What is the molar conc. of the H2So4 in the flask? After I found how many moles there are in 10cm^3, which is 0.02 mol, what is my next step, as because the ...
Sunday, December 30, 2012 at 3:36pm
chemistry
Only pure substance are homologous,true or false? Can you please explain too?
Tuesday, December 25, 2012 at 1:36pm
chemistry
Given that the pH of a substance is 1.0, what is the [H+]? A. 0.0 mol/L B. .1 mol/L C. 2.4 mol/L D. 7.5 mol/L B
Monday, December 17, 2012 at 2:21pm
chemistry *Poorly defined commonly used question
"Why are active on-duty firefighters likely to experience the adverse health effects from inhaling 300 ppm of carbon monoxide faster than nonactive off-duty firefighters who inhale the same concentration of the same substance? Explain your answer using the chemicals/...
Sunday, December 16, 2012 at 5:20pm
Math
In 10 years, 25% of a radioactive substance decays. What is its half-life? A. 25 years B. 24 years C. 20 years D. 29 years
Friday, December 14, 2012 at 2:34pm
Algebra
In 10 years, 25% of a radioactive substance decays. What is its half-life? A. 25 years B. 24 years C. 20 years D. 29 years
Wednesday, December 12, 2012 at 6:54pm
chemistry
hey guys need some help here!!! if 0.250mol of CO and 0.250mol of H2O were combined in a 125mL flask and the reaction allowed to reach equilibrium . Kc= 1.56. write the equ expression and calculate each substance Co(g) +H2O(g) .... Co2(g) +H2(g)
Tuesday, December 11, 2012 at 6:18pm
Science- Chemistry
Determine the type of bonding in each substance. a. Zinc, Zn (s) b. Propane, C3H8 (l) c. Calcium Carbonate, CaCO3 (s)
Tuesday, December 11, 2012 at 9:16am
Physics
I'm also stumped by this one: 3. A bimetallic strip (117 cm by 1 cm by 0.01cm) has aluminum (a = 23x10^-6 1/Celsius) on one side and has steel (a= 12x10^-6 1/Celsius) on the other. It is perfectly straight at room temperature (20 celsius). What change in temperature is ...
Tuesday, December 11, 2012 at 12:24am
Chemistry
please explain how % error and % yield would have effected the mass/moles of a substance in a reaction in a lab. In this case mass/moles of NaCl. NaHCO3+ HCl--> NaCl + CO2 + H2O
Monday, December 10, 2012 at 10:51pm
Chemistry
The figure below is a heat curve for an unknown outerspace substance discovered by the Mars rover. By understanding the heat curve, scientists can make inferences about the composition of the planet. What is the temperature of fusion, Tfusion, and vaporization, Tvapor, for ...
Sunday, December 9, 2012 at 6:20pm
Chemistry
Write a balance equation for the reaction of nitric acid (HNO3) with each base solution : [1]. NaHCO3, [2]. MgCO3. ( Please include the phases of the substance)
Saturday, December 8, 2012 at 9:20am
English - ms. sue
ms. sue my sister write out story here it is. On Monday she looked in her mailbox, although she had no reason to expect a letter so soon. But there it was, a small, square car. She held it in her two hands, testing its weight. It was an invitation to an exhibition of drawings ...
Thursday, December 6, 2012 at 8:46pm
pharmaceutical chemistry
when is a substance classified as pharmaceutical aid or necessity?PLEASE HELP ME :)THANKS A LOT.
Thursday, December 6, 2012 at 7:00am
Chemistry (kinetics)
None of the orders in this reaction were 0 order; however, reactions can be 0 order. Using the idea of a reaction mechanism and rate limiting step, explain how a reaction can be 0 order for a substance.
Wednesday, December 5, 2012 at 9:44pm
Science
A radioactive substance is found to register 1000 counts per second on a Geiger counter. Twenty-four hours later it registers 125 counts per second. What is its half-life?
Wednesday, December 5, 2012 at 9:09pm
Chem
upon cumbustion of a 0.144g sample of Mg, 0.090g of O2 is used. Though the sample likly contains impurites (substance other than Mg). What is the percent of imputities by mass?, please show the steps I'm really confused with this one. Thank you
Wednesday, December 5, 2012 at 5:43pm
Science
If a 20 gram sample of a radioactive substance has a half-life of 6000 years, how many grams would be present after 18000 years?
Wednesday, December 5, 2012 at 4:21pm
Physical Science- Help Please!
Suppose that you are given a 100 gram sample of a radioactive substance with a half-life of 32 days. How many grams will be left after 192 days?
Wednesday, December 5, 2012 at 4:13pm
chemistry
upon cumbustion of a 0.144g sample of Mg, 0.090g of O2 is used. Though the sample likly contains impurites (substance other than Mg). What is the percent of imputities by mass?, please show the steps I'm really confused with this one. Thank you
Wednesday, December 5, 2012 at 10:03am
college chemistry
what is the specific heat of a substance that required 800 joules of heat to raise the temperature of 50 grams of it from 20 degrees Celsius to 30 degrees Celsius?
Tuesday, December 4, 2012 at 11:13pm
Science
Which property can be used to help identify an unknown substance? Specific Heat combustion temperature Tyndall effect
Tuesday, December 4, 2012 at 12:21pm
ap chem
A calorimeter contains 20.0 of water at 12.5 . When 2.20 of (a substance with a molar mass of 59.0 ) is added, it dissolves via the reaction and the temperature of the solution increases to 27.5 . Calculate the enthalpy change, , for this reaction per mole of . Assume that the...
Monday, December 3, 2012 at 3:38pm
ap chemistry
A calorimeter contains 20.0 of water at 12.5 . When 2.20 of (a substance with a molar mass of 59.0 ) is added, it dissolves via the reaction and the temperature of the solution increases to 27.5 . Calculate the enthalpy change, , for this reaction per mole of . Assume that the...
Monday, December 3, 2012 at 2:11pm
ap calculus
suppose that the amount in grams of a radioactive substance present at time t (in years) is given by A (t) = 160e-.70t. Find the rate of decay of the quantity present at the time when t = 4
Sunday, December 2, 2012 at 9:07pm
20 question please check my answers
1. A sickness resulting from eating food that is not safe to eat empty-calorie foods nutrition foodborne illness nutrient density 2. A nutrient that helps control the amount of fluid in your body sodium calorie protein nutrition 3. A measure of nutrient content relative to ...
Friday, November 30, 2012 at 2:34pm
English and Grammar
first draft of my report and i need help in improving this. i didnt made up all the information here all comes from a book. Dissociative identity disorder is defined in the DSM-IV-TR as the presence of two or more personality identities that repeatedly take control of one...
Friday, November 23, 2012 at 12:27pm
How do I calculate the number of atoms in a compou
I have the mass of the amount of substance, and the molar masses. How do I do this? Is this the same as calculating the number of molecules/ formula units? Also, I know the number of atoms for each element in the compound (It made me calculate that before)
Monday, November 19, 2012 at 11:48pm
chemistry
How do I calculate the number of atoms in a compound (not an element)? I have the mass of the amount of substance, and the molar masses. How do I do this? Is this the same as calculating the number of molecules/ formula units? Also, I know the number of atoms for each element ...
Monday, November 19, 2012 at 11:44pm
physics
Calculate the net charge on a substance consisting of a combination of 8.9 × 10 13 protons and 2.6×10 13 electrons. The elemental charge is 1.6 × 10 −19 C. Answer in units of C
Sunday, November 18, 2012 at 1:43pm
health help me
1. Starches and sugars that provide energy (1 point)kidneys enzymes carbohydrates vitamins 2. The system that removes waste from the body and controls the body's water levels (1 point)excretory digestive system liver kidneys 3. Organs that remove waste material, including ...
Saturday, November 17, 2012 at 9:23pm
chemisrty
When a substance changes from one phase to another, which of the following occurs? the substance loses or gains heat the average kenetic energy of the substance changes the temperature of a substance changes the molecular motion of a substance changes
Friday, November 16, 2012 at 11:14am
Chemistry
The question representing the production of tetraphosphorus trisulfide (P4S3), a substance used in some match hears, is 8P4 + 3S8 ---> 8P4S3. Determine if each of the following statements is correct. If the statement is incorrect, rewrite it to make it correct. a. To ...
Wednesday, November 14, 2012 at 11:05pm
science
what is a form of energy that is always transferred from a warmer substance to a cooler one?
Wednesday, November 14, 2012 at 8:31pm
Pre-calculus
On a chicken farm, the poultry is given a healthy diet to gain weight. The chickens have to consure a minimum of 15 units of substance A and another 15 units of substance B. In the market there are only two classes of compounds: Type 1, with a compoistion of one unit of A to ...
Monday, November 12, 2012 at 1:00pm
chemistry
Which of the following is generally defined as a substance composed of molecules in which two or more nonmetallic elements are joined? A. Binary compound B. Ionic compound C. Molecular compound D. Ternary compound I think A
Saturday, November 10, 2012 at 6:40pm
chemistry
Which of the following is true of a substance with a pH of 11.0? A. The substance is an acid. B. The substance is a base. C. The substance is neutral. D. The substance is a transition metal. I think A
Saturday, November 10, 2012 at 3:28pm
calculus
A sample of a radioactive substance decayed to 94.5% of its original amount after a year. (Round your answers to two decimal places.) (a) What is the half-life of the substance? (b) How long would it take the sample to decay to 65% of its original amount?
Friday, November 9, 2012 at 6:00pm
Chemistry
find the volume of 56.4 g of a substance that has a density of 2.42 g/mL
Thursday, November 8, 2012 at 5:11pm
math
what is the mass of 12.0 ml of a substance with the density of 0.922 g/cm3? A. 1.11g B. 0.11g C. 11.1 g I think C.
Wednesday, November 7, 2012 at 3:44pm
math
what is the specific gravity of a substance that has a density of 1.59 g/cm3? A. 1.59 g/mL B. 1.59 g C. 1.59 D. 1.59 mL I think B.
Wednesday, November 7, 2012 at 3:17pm
science
what property must a substance have if you want to use the substance to make an aqueous solution
Tuesday, November 6, 2012 at 5:41pm
science
The density of a substance with a mass of 90g is 2 g/cm cubed. What is the volume?
Tuesday, November 6, 2012 at 11:04am
Chemistry HELP ASAP
A Gouy balance is used to determine the magnetic susceptibility of a substance. A strong electromagnet is placed next to the sample, which is on a balance. If the sample is paramagnetic, the mass reading of the balance will increase when the field is switched on. Based on ...
Monday, November 5, 2012 at 11:45am
Chemistry
A Gouy balance is used to determine the magnetic susceptibility of a substance. A strong electromagnet is placed next to the sample, which is on a balance. If the sample is paramagnetic, the mass reading of the balance will increase when the field is switched on. Based on ...
Sunday, November 4, 2012 at 10:24pm
biochemistry
Enzyme X is a highly pigmented protein that imparts the characteristic color to certain blue-green algae. It also facilitates a reaction necessary to the survival of this species; we can follow the kinetics of this reaction by measuring the conversion of Substance X to ...
Saturday, November 3, 2012 at 9:01am
biochemistry
Enzyme X is a highly pigmented protein that imparts the characteristic color to certain blue-green algae. It also facilitates a reaction necessary to the survival of this species; we can follow the kinetics of this reaction by measuring the conversion of Substance X to ...
Friday, November 2, 2012 at 6:03am
7th grade health please Ms. Sue?
Hi! Sorry, I don't know what subjects you teach, but can you check my answers please? 1. Starches and sugars that provide energy (1 point) kidneys enzymes carbohydrates vitamins 2. The system that removes waste from the body and controls the body's water levels (1 ...
Wednesday, October 31, 2012 at 7:32pm
Chemistry
You have amisture that is 0.100mol/L in each of the following ions: Cl-, Br-, and I-. (a) Which substance will precipitate first? AgCl, AgBr, AgI? (b)what is the concentration of Ag+ required to start the precipitation of the first substance? ksp (AgCl)= 1.77*10^-10 ksp (AgBr...
Monday, October 29, 2012 at 12:25pm
physical science
A substance whose 0xidation number decreases during a chemical reaction
Sunday, October 28, 2012 at 8:35am
Chemistry - Final Temperature
An unknown mass of each of the following substances, initially at 23.0C, absorbs 1910 J of heat. The final temperature is recorded as indicated. Find the mass of each substance. sand (Tf=62.0C) ethanol (Tf=44.1C) water (Tf=32.1C)
Sunday, October 28, 2012 at 8:11am
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