Friday
July 31, 2015

Homework Help: Science: Chemistry

Recent Homework Questions About Chemistry

Chemistry
The hydroxide ion reacts with the H2PO2 ion according to the following equation: OH^- + H2PO2^- > HPO2^-2 + H2 The rate law for this reaction rate is R=k[OH^-]^2[H2PO^-2]. What will be the change in the reaction rate if the H2PO2 ion concentration is doubled. What will the ...
Thursday, July 9, 2015 by Anonymous

chemistry
The synthesis of a certain drug can be carried out with 91.7% yield. In one experiment 14.8 g of the drug was obtained. What was the theoretical yield for this experiment?
Thursday, July 9, 2015 by Linda

Chemistry
How is the enthalpy change for a reaction related to the enthalpy of the reactants and products? Is it that the enthalpy for the reactants and products equals the enthalpy change for the reaction?
Thursday, July 9, 2015 by Anonymous

Chemistry
What is the octet rule? How does the rule explain the common ion of fluorine and of calcium? The octet rule is when an element contains 8 valence electrons. The rule explains the common ions of fluorine and calcium to show how much is needed to gain/lose electrons to get that ...
Thursday, July 9, 2015 by Sam

chemistry
. An enzyme-catalyzed reaction was carried out in a 0.2M �Tris� buffer, pH 7.8. As a result of the reaction, 0.03 mole/liter of H+ was produced. (pKa of Tris =8.1) (a) What was the ratio of Tris+ (conjugate acid) / Triso (Conjugate base) at the start of the ...
Thursday, July 9, 2015 by pankaj

Chemistry
If the electromagnetic radiation used to send television signals have a frequency of 3.0 * 10^9 Hz, what is its wavelength? I forget how to do a problem like this. Just taking a guess, is this somewhat a conversion equation?
Wednesday, July 8, 2015 by Jack

Chemistry
What volume, in liters, of 1.04 M KOH solution should be added to a 0.116 L solution containing 10.08 g of glutamic acid hydrochloride (Glu, FW = 183.59 g/mol; pKa1 = 2.23, pKa2 = 4.42, pKa3 = 9.95) to get to pH 10.15?
Wednesday, July 8, 2015 by K

Chemistry
What is the catalyst of N2(g)+3H2(g) to give(double arrow) 2NH3(g)?
Wednesday, July 8, 2015 by Omoniyi Ayodeji

Chemistry
For an equation N2(g)+3H2(g) double arrowed to give 2NH3(g) what is the catalyst?
Wednesday, July 8, 2015 by Omoniyi Ayodeji

chemistry
If a 0.01M Mn(NO3)2 solution has an ammonia concentration of 6.0M, would a precipitate form? Calculate the ion product and compare to Ksp.
Wednesday, July 8, 2015 by jojo

chemistry
Treatment with sodium borohydride converts aldosterone A in to an optically inactive alditol. Ruff degradation of A from B, whose alditol is optically inactive. Ruff degradation of B from D - glycerol dehydration. Identify A and B. Please help urgently. Please!!!!!
Wednesday, July 8, 2015 by sanjay

chemistry
at what ratio should I titrate sterile water with 50% MgSO4 to get 20% MgSO4.i mean the units of water to those of MgSO4
Wednesday, July 8, 2015 by myk

Chemistry
What is the volume occupied by 12.9 g of argon gas at a pressure of 1.30 atm and a temperature of 318 K ?
Wednesday, July 8, 2015 by Dustin

Chemistry
How does the kinetic-molecular theory help explain the difference between solids, liquids, and gases? I don't know how to really answer this question because the theory only talks about gases, unless I am looking at the wrong one. I tried to look it up swell and all I got ...
Wednesday, July 8, 2015 by Jack

chemistry
Treatment with sodium borohydride converts aldosterone A in to an optically inactive alditol. Ruff degradation of A from B, whose alditol is optically inactive. Ruff degradation of B from D - glycerol dehydration. Identify A and B.please give satisfactory answer
Tuesday, July 7, 2015 by sanjay

Chemistry-History-ish
Describe 3 experiments, run prior to 1930, and the types of energies/particles used to probe the structure of the atom. What did each experiment investigate? Include the names of the scientists associated with each experiment in your answer Would this be right? Prior to 1930, ...
Tuesday, July 7, 2015 by Anonymous

Chemistry
When naming a molecular compound, such as CO, would I write it as mono carbon monoxide or carbon monoxide? My textbook has the rule written as prefix+1st element prefix+2nd element, but I am not sure if the mono applies to the carbon or not.
Tuesday, July 7, 2015 by Jack

Chemistry
Explain the basic format and the steps needed to name an ionic compound composed of a cation that has a possibility of existing in more than one oxidation state. Is this right: There are four prefixes used when naming ionic compounds: per__ate, -ate, -ite, and hypo__ite. ...
Tuesday, July 7, 2015 by Chris

chemistry
The edge length of face centered unit cubic cell is 508pm.if the radius of the cation is 110 pm,the radius of anion is
Tuesday, July 7, 2015 by tanya

Chemistry
How much heat is needed to convert 10g ice to 10g water vapor?
Tuesday, July 7, 2015 by Drew

Chemistry
Diatomic O2 can react with the element magnesium to form magnesium oxide (MgO). The balanced chemical equation is: If 4 moles of magnesium totally reacted with more than enough O2, how many moles of MgO would be expected to form?
Tuesday, July 7, 2015 by Anonymous

chemistry
Treatment with sodium borohydride converts aldosterone A in to an optically inactive alditol. Ruff degradation of A from B, whose alditol is optically inactive. Ruff degradation of B from D - glycerol dehydration. Identify A and B
Tuesday, July 7, 2015 by sanjay

chemistry
A piece of iron (Cp = 0.450 J/(gi°C)) that has a mass of 21.5 g and an initial temperature of 100.0°C is submerged in X g of water (Cp = 4.184 J/(gi°C)) at 20.0°C. The temperature of the system (iron and water) changes to 21.4°C. What is the value of X?
Tuesday, July 7, 2015 by ken

chemistry
Consider the following reagents: zinc, copper, mercury (density: 13.6 g/mL), silver nitrate solution, nitric acid solution. a. Given a 500-mL Erlenmeyer flask and a balloon can you combine two or more of the foregoing reagents to initiate a chemical reaction that will inflate ...
Tuesday, July 7, 2015 by kate

Chemistry
Give an example of one polyatomic cation and one polyatomic anion. Show how these ions combine to make a compound. My thinking: Cation-ClO Anion-K How they form, I don't know?
Monday, July 6, 2015 by Isaac

Chemistry
What would the partial pressure of hydrogen in the gas collection tube be if the water in the tube was 25.0 mm above the water level in the beaker, the room pressure was 655 mm Hg, and the temperature of the room was 22 degrees C?
Monday, July 6, 2015 by Jenny

Chemistry
When is the term, formula unit, useful? Is it when trying to figure out the empirical formula?
Monday, July 6, 2015 by Isaac

Chemistry
What are the pros and cons of using the lewis structure? What I have so far is that it shows the shape of the compound.
Monday, July 6, 2015 by Anonymous

Chemistry
How many moles are there in 0.7g of CFC's
Monday, July 6, 2015 by Fida

Chemistry
A 150.0 mL sample of a 1.50 M solution of CuSO4 is mixed with a 150.0 mL sample of 3.00 M KOH in a coffee cup calorimeter. The temperature of both solutions and the calorimeter was 25.2°C before mixing and 31.3°C after mixing. The heat capacity of the calorimeter is 24...
Monday, July 6, 2015 by Richard

physical sciences(chemistry)
Explain why solution turns blue by referring to the relative strength of oxidising agent?
Monday, July 6, 2015 by Xalati

chemistry
1. Which example has particles that can be drawn closer to occupy smaller volume? a. fruit juice b. block of wood c. air inside the syringe d. ice cube 2. Which of the following phenomena does NOT involve the application of gas pressure? a. burning fuels b. falling leaves c. ...
Monday, July 6, 2015 by ken

Chemistry
Heat is applied to an ice cube in a closed container until only steam is present. Draw a representation of this process. What happens to the size of the molecules and total mass of the sample?
Monday, July 6, 2015 by Person

Chemistry-Molecular models
Select a compound and explain the advantages and disadvantages of using ball-an-stick, space-filling, and lewis structure to represent compound. What I have so far: The advantages for all the models are that you can see the shape of the atoms, but unlike the ball-and-stick and...
Sunday, July 5, 2015 by Anonymous

Chemistry
Explain how the formulas for H2O and NaCl provide different information about the composition of these two compounds. What I think: For every 1 atom of oxygen, there are 2 atoms of hydrogen. For every one atom of sodium there is one atom of chlorine.
Sunday, July 5, 2015 by Anonymous

Chemistry
A student mixes 764 mL of water and 476 mL of 1.00 x 10-5 M orange food dye solution. What is the concentration of this new dilute solution of orange food dye?
Sunday, July 5, 2015 by George

emmanuel college
Chemistry A is a solution of H2SO4 containing 2.5g in 500cm3
Sunday, July 5, 2015 by gboyega

chemistry
describe how you would prepare 500mL of 0.25 M NaNO3 solution?
Saturday, July 4, 2015 by siti

Chemistry
Propose three models that explain Thomson’s findings and evaluate them. To be complete you should include Thomson’s findings.
Saturday, July 4, 2015 by Kristina

Chemistry
These are all review questions for my summer assignment. Do not know: !) Explain what an ionic lattice is and include a diagram. 2)Draw a diagram to show how Na and CL2 combine to form NaCl Unsure: !)Select two compounds and explain when Roman numerals are used in the name of ...
Saturday, July 4, 2015 by Issac

Chemistry
Which of the following are true about the use of aluminum chloride in the Friedel-Crafts acylation reaction? Note that there may be more than one correct answer. Aluminum chloride removes chloride from acetyl chloride to generate a nucleophile that can attack the ring of ...
Saturday, July 4, 2015 by JOHN K

chemistry
According to the American Insurance Companies, on average, a vehicle is driven 12,000 miles per year. In the chemical equation below, gasoline is given as octane, or C8H18. Assume the vehicle gets 22.0 miles per gallon. The density of octane is 0.703 g/mL. 2 C8H18 + 25 O2 &#...
Saturday, July 4, 2015 by lollo

Chemistry
The diameter of a hydrogen nucleus is 1.0 X 10 -3 pm and its mass is 1.67 X 10 -24 g. What is the density of the nucleus in grams per cubic centimeter? Assume the nucleus is a sphere with volume = 4/3pie r3.
Saturday, July 4, 2015 by Kristina

Chemistry
Will addition of water to vinegar affect the determination of its concentration? Why?
Friday, July 3, 2015 by Hannah

Chemistry
Noble gases are the least reactive because they have a perfect 8 valence electrons. Or is it because they do not have any unpaired electrons like the rest of the elements.
Friday, July 3, 2015 by Joey

Chemistry
A helium balloon contains 0.50 g of helium. Given the molecular weight of helium is 4.0 g/mol, how many moles of helium does it contain?
Friday, July 3, 2015 by Anonymous

Chemistry
Calculate the volume of solution that has a vapour pressure of 31.27 mbar and contains 84.3g of sucrose, at a temperature of 25.0C. The vapour pressure of pure water at 25.0C is 31.7mbar, the density of water is 1.00g/mL, and assume no change in volume occurs upon dissolution.
Friday, July 3, 2015 by B

Chemistry
If I were to explain to someone about how to find a charge of an element, would anyone agree with this: The charge of an element is determined by the gain or lose of electrons. Depending on how close they are to the left/right side of the periodic table concludes their charge...
Thursday, July 2, 2015 by Joey

Chemistry
1) Which group of elements is the least reactive? Explain why. 2) What properties distinguish metalloids from other elements? 3)Explain how to predict the charge usually observed for a monatomic ion.
Thursday, July 2, 2015 by Anonymous

Chemistry
How many GRAMS of boron are present in 3.54 moles of boron trifluoride
Thursday, July 2, 2015 by Anonymous

Algebra
70 students are studying mathematics,physics & chemistry.40 students study mathematics,35 study physics and 30 study chemistry.15 students are studying all the three subjects.How many students are studying exactly two of the subjects
Thursday, July 2, 2015 by Anika

chemistry
calculate the molal solution depression constant of a solvent which has freezing point 16.6° and latent heat of fusion 180.75J/g 3.3 3.86 2.9 38.6
Thursday, July 2, 2015 by please............

Chemistry
Predict the answer to each question according to trends in the periodic table. Justify each answer based on the locations of the elements on the periodic table and/or the shell model. a. Which has a greater atomic radius, Al or Cl? b. Which has a greater ionic radius, Na or S...
Wednesday, July 1, 2015 by Madison

Chemistry
How many grams of NaOH are needed to make 450mL of a 2.5%(m/v) NaOH solution?
Wednesday, July 1, 2015 by Telimm

Chemistry
What is the net ionic equation, including phases, for the reaction of AgNO3(aq) with K2SO3(aq)
Wednesday, July 1, 2015 by Patty

Chemistry
How many grams of NaCl are present in 1.5L of a 0.25M NaCl solution?
Wednesday, July 1, 2015 by Telimm

Chemistry
Analyze each table of ionization energy data (in kJ/mol) to identify each element. a. A Period 3 element (1 point) IE1: 496, IE2: 4562, IE3: 6910, IE4: 9453, IE5: 13354, IE6: 16613, IE7:20117 b. A Period 5 element (1 point) IE1: 403, IE2:2633, IE3: 3860, IE4:5080, IE5: 6850, ...
Wednesday, July 1, 2015 by Madison

Chemistry
I know Chadwick found/discovered the neutron, but my textbook does not state what experiment he did to find it. Can someone briefly state what he did to find the atom?
Wednesday, July 1, 2015 by Anonymous

Chemistry/reading
Although Rutherford's model was highly successful, scientists realized that it was incomplete. For example, hydrogen atoms contain one proton, and helium atoms contain 2, yet a hydrogen atom has only 1/4 the mass of a helium atom. I'm not comprehending what my textbook...
Wednesday, July 1, 2015 by Anonymous

Chemistry
Describe 3 experiments, run prior to 1930, and the types of energies/particles used to probe the structure of the atom. What did each experiment investigate? Include the names of the scientists associated with each experiment in your answer.
Wednesday, July 1, 2015 by Anonymous

Chemistry
Determine what this molecule should really be named. 2,2-ethylpent-3-ene I get the answer 2,2-diethylpent-3-ene. Why would the answer be: 4-ethyl-4-methylhex-2-ene
Wednesday, July 1, 2015 by Sara

chemistry
A sample of ammonium phosphate(NH4)3PO4 contains 3.18 moles of hydrogen atoms. The number of moles of oxygen atoms in the sample is (1)0.265 (2)0.795 (3)1.06 (4)4.00
Wednesday, July 1, 2015 by Anonymous

chemistry
A sample of ammonium phosphate (NH4)3PO4 contains 3.18 moles of hydrogen atoms then the on. of moles of oxygen atoms in the sample is
Wednesday, July 1, 2015 by Priti

chemistry
Nitrogen forms five compounds with oxygen in which1.0g of nitrogen combines with0.572,1.14,1.73,2.28,2.85 of oxygen respectively. verify law of multiple proportions.
Tuesday, June 30, 2015 by gurlabh

Chemistry
Draw a diagram to illustrate your explanation of how the charge of a single electron was determined. I'm suppose to draw a picture to show how they determined electrons were negative, but am unsure of what to draw for it. One of my ideas is to draw a cathode ray tube with ...
Tuesday, June 30, 2015 by Anonymous

Chemistry
How does a cathode ray tube work? What I want to write: Energy is given to the cathode , thus allowing an energy beam to be crated between the positive charge on one end of the tube, and the negative charge on the other end. Can I add anymore? Also, would it be reasonable to ...
Tuesday, June 30, 2015 by Anonymous

St. Basil's school: Chemistry
The pressure of a gas having volume 1800ml. Originally occupying 300ml. at 6 atms. Pressure.
Tuesday, June 30, 2015 by Richa

Chemistry
Calculate the number of moles of CuSO4 contained in 100 ml of 1mole CuSO4 solution. Also find the number of SO4 ~~ ions in it .?
Tuesday, June 30, 2015 by Awadhesh kumar

Chemistry
Calculate the volume occupied by 5.25 g of nitrogen at 26*c [temperature] and 74.2 cm of pressure.?
Tuesday, June 30, 2015 by Awadhesh kumar

Chemistry
A is a solution of hcl containing 7.30gdm^-3 and B is a solution of X2CO3 containing 10.6gdm^-3.calculate the concentration of A in Moldm^-3
Monday, June 29, 2015 by Caleb

Chemistry Subatomic particles
What data led to the need for change in Daltons ideas?
Monday, June 29, 2015 by Anonymous

Chemistry Subatomic particles
What data led to the need for change in Daltons ideas?
Monday, June 29, 2015 by Anonymous

Chemistry Subatomic particles
Fill in the chart (Numbers correspond to each other[I.E 1 in 1st group connects with 1in 2nd]) Subatomic particle found 1.Proton 2.Neutron 3.Electron Scientist 1.Rutherford 2.Chadwick 3.Thomson Experiment 1.Gold Foil Experiment? 2.? 3.Cathode Ray Tube Data Supporting Discovery...
Monday, June 29, 2015 by Joey

Organic Chemistry
Please help! Thank you! Alcohols can act either as weak acids or as weak bases, just as water can. Show the reaction of methyl alcohol, CH3OH, with a strong base such as Na+ -NH2
Monday, June 29, 2015 by Anonymous

Chemistry
How come lead is denser than copper though more copper atoms can fit into a same size cube than lead atoms can?
Monday, June 29, 2015 by Joey

Chemistry
When heated to 350. ∘C at 0.950 atm, ammonium nitrate decomposes to produce nitrogen, water, and oxygen gases: 2NH4NO3(s)→Δ2N2(g)+4H2O(g)+O2​(g) Using the ideal gas law equation, calculate the volume, in liters, of water vapor produced when 21.8 g of ...
Monday, June 29, 2015 by Telimm

Chemistry
Copper and lead had different densities. Sketch a diagram at the particular nature of matter level showing the atoms of a small cross section of copper and lead. Use this diagram to explain why lead is denser than copper. I couldn't find any pictures or see anywhere in my ...
Monday, June 29, 2015 by Anonymous

Chemistry
472 mL of H2 was collected over water when 1.256g Zn reacted with excess HCl. The atmospheric pressure during the experiment was 754 mmHg and the temp was 26C. What is the pressure in atm of the dry hydrogen gas in the mixture. I don't know how to answer this.
Monday, June 29, 2015 by Stan

Chemistry
What volume of 0.5M NaOH must be added to 50mL of .0.1M benzoic acid to make 100.0 mL of 0.05 M benzoate buffer that is pH 4.5?
Monday, June 29, 2015 by Kathys

Chemistry
If the mole fraction of ethanol in aquas solution is 0.05 . Calculate morality of solution ? Explain it's.
Monday, June 29, 2015 by Awadhesh kumar

Chemistry
What volume of 0.5M NaOH must be added to 50mL of .0.1M benzoic acid to make 100.0 mL of 0.05 M benzoate buffer that is pH 4.5?
Monday, June 29, 2015 by Kathy

Chemistry
Consider the reaction: 2Mg + O2 ------> 2MgO The reaction is at equilibrium, the concentration of MgO is found to be 0.5. What is the concentration of Mg and O2? ----------------------------------------​--------------- Keq is not given... using the ICE table, I ended ...
Monday, June 29, 2015 by Annie

Chemistry
Consider the reaction: 2Mg + O2 ------> 2MgO The reaction is at equilibrium, the concentration of MgO is found to be 0.5. What is the concentration of Mg and O2? ----------------------------------------​--------------- Keq is not given... using the ICE table, I ended ...
Monday, June 29, 2015 by Annie

chemistry
10.5 g sample of copper metal at 25.0°C is heated by the addition of 150.0 J of energy. The final temperature of the copper is _____°C. The specific heat capacity of copper is 0.38 J/ goC.
Monday, June 29, 2015 by jennifer

Chemistry
What data led to the development of the Law of Multiple Proportions? Give an example and explain why this law is important in chemistry. Would this be a good answer: John Dalton used the same observations he used for his law of definite proportions to help develop the law of ...
Sunday, June 28, 2015 by Jack

Chemistry
Why aren't the properties of sodium chloride the same as the elements that compose it?
Sunday, June 28, 2015 by Jill

chemistry
In the reaction of sodium metal with chlorine gas to form sodium chloride, how does chlorine form an anion? Write an equation to support your answer. I know that chlorine becomes an anion since it's gaining an electron from sodium, but how do I show that in an equation?
Sunday, June 28, 2015 by Anonymous

chemistry
correct the following examples of gasses to standard temperature. (assume pressure is constant)(STP stands for standard temp and pressure which is 273K and 101kPa, you do no have to think about the pressure for these four but on the last three you will have to so T2 is 273K ...
Sunday, June 28, 2015 by Anonymous

chemistry
A compound is found to contain 15.12 % phosphorus, 6.841 % nitrogen, and 78.03 % bromine by weight. what is the emperical formula
Sunday, June 28, 2015 by Jeremy

general chemistry
P in PCl5 has a trigonal planar right? Cl2=P=Cl2 | Cl1 is it right? help me how to determine the angle
Sunday, June 28, 2015 by faye

chemistry
If 5.40 kcal of heat is added to 1.00 kg of water at 100 degrees celsius, how much steam at 100 degrees celsius is produced?
Sunday, June 28, 2015 by olaf

organic chemistry
whats the difference between inorganic chem and organic chem? im really confuse because mrs. white told us inoraganic is about ionic bonds while organic is about covalent bond. what is the difference between the twooo? please help me
Saturday, June 27, 2015 by ella

Chemistry Stoichiometry
The density of chloroform at a pressure of 220 mmHg and 25 degrees celsius is 1.42 g/L. Calculate the molar mass of chloroform. My set up is: mol*K .289 atm 1 1.42g/L ------------- ------------ ------ --------- .08206Latm 1 298K What I am unsure of is if this is the right way ...
Saturday, June 27, 2015 by Jack

Chemistry
If 100.0 mL of 0.150 M sodium nitrate is added to 50.0 mL of 0.150 M sodium carbonate, what is the resulting molar concentration of the sodium ion?
Friday, June 26, 2015 by John

Chemistry
How would I find the pH of these? I found it for d and e, but I don't know how to do the rest a) 0.25M carbonic acid b) 0.075M CN- c) 0.15M F- d) 0.015M HCl (I got 1.8) e) 0.015 M NaOH (I got 12) f) 0.050 M acetic acid
Thursday, June 25, 2015 by Sara

chemistry
How to distinguish between an acid and an alkali. DO not use indicators
Wednesday, June 24, 2015 by Clive

Chemistry
You may have noticed that when water boils, you can see bubbles that rise to the surface of the water. a. What is inside these bubbles? i. air ii. hydrogen and oxygen gas iii. oxygen gas iv. water gas v. carbon dioxide gas
Wednesday, June 24, 2015 by Anonymous

Chemistry
PCl5 is introduced into an evacuated chamber and comes to equilibrium (see Problem 16.37), at 250◦C and 2.00 atm. The equilibrium gas contains 40.7% Cl2 by volume. (a1) What are the partial pressures of the gaseous components at equilibrium? (a2) From these data, ...
Wednesday, June 24, 2015 by Joe johnson

Chemistry
My question is I need to change to symbol on sodium ion, \rm Na^+, followed by the formula of a sulfate ion, \rm SO_4{}^{2-} Its my first time in chemistry class.
Wednesday, June 24, 2015 by Zulema

Chemistry
You have two beakers, one filled to the 100 mL mark with sugar (mass of sugar 180.0 g) and the other filled to the 100 mL mark with water (m ass of water 100.0 g). You pour all the sugar and all the water together in a bigger beaker and stir until the sugar is completely ...
Wednesday, June 24, 2015 by Kristina

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