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Homework Help: Science: Chemistry

Recent Homework Questions About Chemistry

chemistry
The percentage of nitrogen in magnesium nitride is.?
Thursday, October 13, 2016 by Sai

chemistry
For the elements in row 2 of the PT discover the relationship between ionization and the family number of the element Element. Family. Ionization Ener Lithium. 1 13.6 beryllium. 2. 9.3 boron. 13. 8.3 carbon. 1 4. 11.27 nitrogen. 15 14.53 oxygen. 16. 13.62 fluorine. 17. 17.42 ...
Thursday, October 13, 2016 by lulu

chemistry
When calling the families on the periodic chart by the top or first name in the column, where hydrogen is a non metal, and in family 13, where boron is a metaloid , is it correct to call those families the hydrogen or lithium family or/ and the boron family and for family 14, ...
Wednesday, October 12, 2016 by lulu

Chemistry
How many moles of ions are in 1.0 mol NH4Cl?
Wednesday, October 12, 2016 by Isaiah

Chemistry
Net Ionic equation for 1. Iron(II) Iodide and Magnesium Acetate 2. Ammonium Phosphate and Cobalt(III) Chloride 3. Sodium Acetate and Potassium Chloride These are the only ones I have left on my HW and I can't seem to figure them out would appreciate some help.
Wednesday, October 12, 2016 by Jake

Chemistry
What is the Net Ionic Equation for Nitric Acid and Potassium Carbonate?
Wednesday, October 12, 2016 by Alan

Chemistry
Lactose Aspartame Sucrose Sucralose Saccharin which ones of these are polar, which are non-polar? and what is the structures of them? like their O-H bonds? i found answers to other sugars like glucose and fructose but need help for these
Wednesday, October 12, 2016 by Holfbrincl

Chemistry
What is the concentration in each of the following solutions? A) 240 mL of 0.200 M KNO3 is added to 160 mL of water. B) 2.25g of NaCl is dissolved in 250 ml of water.
Wednesday, October 12, 2016 by Alan

Chemistry
The quantity of Cl- in a water supply is determined by titrating the sample with Ag+. What mass of chloride ion is present in a 10,0g sample of the water if 20.2 ml of 0.100 M Ag+ is required to react with all the chloride in the sample?
Wednesday, October 12, 2016 by Alan

Chemistry
In order to determine the concentration of a solution of Carbonic Acid (H2CO3), a sample was placed in a buret and titrated with 0.1132 M Sodium hydroxide. For the carbonic acid, the initial reading was 11.0ml and final reading was 31.0 ml. For sodium Hydroxide, the initial ...
Wednesday, October 12, 2016 by Brad

Chemistry
A hot lump of 25.6 g of aluminum at an initial temperature of 57.4 °C is placed in 50.0 mL of H2O initially at 25.0 °C and allowed to reach thermal equilibrium. What is the final temperature of the aluminum and water given that the specific heat of aluminum is 0.903 J/(g·°...
Wednesday, October 12, 2016 by Joseoh

Chemistry
Based on the standard reduction potentials given below, which species is most likely to be oxidized? Ag+ + e- → Ag, Eo= 0.80 V Cu2+ + 2e- → Cu, Eo= 0.34 V Zn2+ + 2e- → Zn, Eo= -0.76 V Cd2+ + 2e- → Cd, Eo= -0.40 V I thought the answer would be Zn2+ that'...
Wednesday, October 12, 2016 by James

Chemistry
I need to prepare 500 ml of a 37% w/w solution of sulfuric acid using 96% sulfuric acid in deionized water. I have been shown a bunch of different ways and they all give a different answer and I'm getting frustrated
Wednesday, October 12, 2016 by Pam

Chemistry
Consider a 0.15m calcium chloride aqueous solution a) determine the molarity of all solution. Assume that calcium chloride completely ionizes when dissolved in water. All solutes means all cations and anions. b)
Wednesday, October 12, 2016 by Zai to DrBodd22

chemistry
0.5mols of a mono alkanoicacid weighs 44 grams, determine the molecular formula and name the acid. (show the workings)
Wednesday, October 12, 2016 by EMMANUEL

Chemistry
What are the elements in Group A1 on the periodic table? alkali metals alkali earth metals inner transition metals ** halogens
Wednesday, October 12, 2016 by Selena

Chemistry
How many isomers are there in the following: 1. C2H4O (I was able to draw three.. Two involving a double bond and one involving a ring.) 2. C3H8O (I can only draw one..) 3. C2H4Cl (3 isomers?)
Wednesday, October 12, 2016 by Anonymous

Chemistry
Find dissociation constant of e thanoic acid having concentration 0.2M and degree of dissociation 50%
Wednesday, October 12, 2016 by Anu

chemistry
what happens to the mass of copper when over heated and forms copper(ii) oxide
Wednesday, October 12, 2016 by Khumo

Chemistry
Why sulphur dioxide is not directly dissolve in water?
Wednesday, October 12, 2016 by Tamaq

Chemistry
Why gay lussac's law applicable only for gases and not for solid and liquid??????????!
Wednesday, October 12, 2016 by Tamaq

Chemistry
1. A 0.70 g mixture of Cu and CuO was treated with hydrogen at elevated temperature. CuO was reduced to Cu and water was formed. (a) Write a balanced equation for the reaction. (2 marks)
Wednesday, October 12, 2016 by Lightningtx

algebra homework help
student missed 11 problems on a Chemistry test and received a grade of 65%. If all the problems were of equal value, how many problems were on the test? Round off your answer to the nearest integer. X= # of problems 11= # of missed problems 65% of correct problems 35% of ...
Wednesday, October 12, 2016 by jennifer

algebra
A student missed 11 problems on a Chemistry test and received a grade of 65%. If all the problems were of equal value, how many problems were on the test? Round off your answer to the nearest integer. X= # of problems 11= 3 of missed problems 65% of correct problems 35% of ...
Wednesday, October 12, 2016 by jennifer

Chemistry
How many isomers are there in the following: 1. C2H4O (I was able to draw three.. Two involving a double bond and one involving a ring.) 2. C3H8O (I can only draw one..) 3. C2H4Cl (3 isomers?)
Wednesday, October 12, 2016 by Anonymous

algebra homework help
A student missed 8 problems on a Chemistry test and received a grade of 47%. If all the problems were of equal value, how many problems were on the test? Round off your answer to the nearest integer. My answer is 15 question were on the test is this correct
Wednesday, October 12, 2016 by jennifer

Chemistry
Is carbon dioxide a chemical reaction? Just carbon dioxide itself... (like from fossil fuels, cars, etc.)
Tuesday, October 11, 2016 by Fading

Chemistry
Which is the electrophilic site in the molecule (CH3)2C=O? A. CH3 carbon B. CH3 hydrogen C. C=O carbon D. C=O oxygen I think the answer is D. because oxygen is electronegative and wants electrons thus making it electrophilic. Is this correct?
Tuesday, October 11, 2016 by Anonymous

Chemistry (chromatography)
I had a chromatography experiment for chemistry and here is one of the questions: Did the compounds travel farther in the water or the isopropyl alcohol (rubbing alcohol)? Explain why you think that this is the case. Now, the compounds traveled the farthest in the water but I ...
Tuesday, October 11, 2016 by Fading

Math/Chemistry
Your friend eats 50.0g tuna steak. You find out that the tuna is 0.001% (by mass) mercury. The lethal dose of mercury is 5.5x10^-3 mg of mercury. Should you take your friend to the hospital?
Tuesday, October 11, 2016 by Ray

Chemistry
If you had not quite driven off all the water from the hydrate by the end of the excitement , there may still be water in the crucible at the final weighing , causing the final weight to be higher than expected . Would this cause your calculated waters of hydration /...
Tuesday, October 11, 2016 by Yveline

chemistry
why does line separating solids and liquids have a negative slope for water, while most compounds have a phase diagram with a positive slope?
Tuesday, October 11, 2016 by Anonymous

Chemistry
How would you make .25 Liters of a .1 M MgCl2 solution?
Tuesday, October 11, 2016 by Mayson

Chemistry
After mixing 1 g of 60% ee (+)-Kendomycin with 2 g of 80% ee (+)-Kendomycin, what is the ee of the final mixture? I know the answer is 73% ee, but I don't understand how to get to that answer!
Tuesday, October 11, 2016 by Christina

Chemistry
Which is the electrophilic site in the molecule (CH3)2C=O? A. CH3 carbon B. CH3 hydrogen C. C=O carbon D. C=O oxygen I think the answer is D. because oxygen is electronegative and wants to hog electrons this making it electrophilic. Is this correct?
Tuesday, October 11, 2016 by Nevaeh

Chemistry
25cm3 Of 3g Of Hydrated Sodium Trioxocarbonate (iv) Solution (NaCO3XH2O)per 250cm3 Was Neutralized By 13.20cm3 Of 0.16m Hydrochloric Acid Solution. 1) Write The Equation For The Reaction. 2) Calculate The Conc Of The Base In Mol/dm3. 3) Calculate The Molar Mass Of The Base. 4...
Tuesday, October 11, 2016 by Loveth

Chemistry
25cm3 Of 3g Of Hydrated Sodium Trioxocarbonate(iv) Solution (NaCO3XH2O)Per 250cm3 Was Neutralized By 13.20cm3 Of 0.16m Hydrochloric Acid Solution. Write The Equation For The Reaction. Calculate The Conc Of Base In Mol/dm3. Calculate The Molar Mass Of The Base. The Value Of X. ...
Tuesday, October 11, 2016 by Loveth

Chemistry
Please Write Out The Equation Of This Reation NaCO3XH2O
Tuesday, October 11, 2016 by Loveth

Chemistry
A calcium iodide solution is made by mixing 0.520g of calcium iodide with 12.0ml of water. 1) Determine the moles of calcium iodide used to make the solution 2) Determine the mass of solvent used to make the solution. Assume that the density of water is 1.000g/ml. 3) Determine...
Tuesday, October 11, 2016 by Faith 1

college chemistry
Predict two new ionic compounds that may form after you mix these sodium phosphate and calcium nitrate solutions. Write a balanced equation to show which ions would collide and what compound will form.
Tuesday, October 11, 2016 by lesley

Chemistry
If a solution containing 107.68 g of mercury(II) perchlorate is allowed to react completely with a solution containing 17.796 g of sodium sulfide, how many grams of solid precipitate will be formed?
Tuesday, October 11, 2016 by Julia

Chemistry
Find the ratio of the pH of solution (I) containing 1 mol of CH3COONa and 1 mol of HCl in 1L and solution (II) containing 1 mol of CH3COONa and 1 mol of CH3COOH in 1L
Tuesday, October 11, 2016 by Sandu

Chemistry 2
we make a solution of water and ethylene glycol c2h4(oh)2 which contains 24 g of the glycol for each 74 g of water. What is the boiling point of ethylene?
Tuesday, October 11, 2016 by Adam

Chemistry
Equal volume. Of mixture of 2 solution with ph = 2 and ph = 12 find out the ph of the resultant mixture
Tuesday, October 11, 2016 by Akansha

Chemistry
Calculate the volume of 0.05 M NaOH which must be added to 100 cm3 of 0.05 M methanoic acid to obtain a buffer of pH 4.23. (Ka for methanoic acid = 1.77 x 10-4)
Tuesday, October 11, 2016 by Carlos

chemistry
Write balance half ionic equation when aluminum oxide is decomposed to aluminum and oxygen.
Tuesday, October 11, 2016 by sheena

chemistry
A sample on analysis shows 50% cao what will be the % of calcium carbonate in it
Monday, October 10, 2016 by HASSAN zia

Chemistry
A stock solution of sulfuric acid must be diluted by adding 25.0mL of 7.50M H2SO4 to enough water to make 500mL of diluted soultion. What is the concentration of the diluted solution?
Monday, October 10, 2016 by Anonymous

Chemistry
If 8.723 grams of sodium bicarbonate are dissolved in water to produce a 250.0mL solution, what is the morality of this solution?
Monday, October 10, 2016 by Anonymous

Chemistry
On a practice exam, we have a question that says "How many enantiomers does kendomycin have?" It says the answer is 1, but I don't understand why? (You probably have to google a picture of kendomycin!!)
Monday, October 10, 2016 by Kyla

Chemistry
If 8.723 grams of sodium bicarbonate are dissolved in water to produce a 250.0mL solution, what is the molarity of this solution?
Monday, October 10, 2016 by Maegan

chemistry
Which one of the following complex ions has an optical isomer? a. [Zn(phen)2]2+ b. [Cu(CN)4]2– c. [Co(H2O)4en]2+ d. [Zn(NH3)2en]2+ e. [Ni(en)3]2+ is the answer a) im confused as to what phen and en stand for.
Monday, October 10, 2016 by chemi

Chemistry
On a practice exam, we have a question that says "How many enantiomers does kendomycin have?" It says the answer is 1, but I don't understand why?
Monday, October 10, 2016 by Kyla

organic chemistry
Free-radical halogenation can occur with chlorine and a source of direct UV radiation or sunlight. Chlorination of 2,4-dimethylpentane via radical halogenation leads to the formation of all three of the below products. Estimate the relative percentages of each product that ...
Monday, October 10, 2016 by Anonymous

Chemistry
1) The letter "p" in the symbol 4p^3 indicates the ___. A) spin of an electron B) orbital shape*** C) principal energy level D) speed of an electron 2) If the spin of one electron in an orbital is clockwise, what is the spin of the other electron in that orbital? A) Zero B) ...
Monday, October 10, 2016 by Mary

Chemistry
A lead fishing weight cotains 0.12 mol of lead atoms. What is its mass?
Monday, October 10, 2016 by Denise

Chemistry
What would be the wavelength of a 50-gram golf ball traveling at 40 meters/second? Is this large enough to be observable?
Monday, October 10, 2016 by Emily

Chemistry
CO2(g)+CaSiO3(s)+H2O(l)→SiO2(s)+Ca​(HCO3)2(aq) Balance using smallest multiples
Monday, October 10, 2016 by Anonymous

Science (Chemistry)
"Calculate the amount of heat (kcal) released when 18.0 g (grams) of steam are condensed at 100.0 C and the resulting water is frozen and cooled to 25.0 C." The only problem that I'm having is the amount of physical and temperature changes that there are. I'm new and still ...
Monday, October 10, 2016 by Sebastian

Science (Chemistry)
"Calculate the amount of heat (kcal) released when 18.0 g (grams) of steam are condensed at 100.0 C and the resulting water is frozen and cooled to 25.0 C." The only problem that I'm having is the amount of physical and temperature changes that there are. I'm new and still ...
Monday, October 10, 2016 by Sebastian

chemistry
What volume of air is needed to burn an entire 60-L (approximately 16-gal) tank of gasoline? Assume that the gasoline is pure octane, C8H18. Hint: air is 20% oxygen by volume, 1 mol of a gas occupies about 25 L at room temperature, and the density of octane is 0.70 g/cm3.
Sunday, October 9, 2016 by Joe Smith

chemistry
Consider the following reaction. 4Fe + 3O2 2Fe2O3 a. How many moles of O2 are required to react completely with 46.7 mg of Fe? How many grams Fe2O3, are produced from the complete reaction of 20.1 g of Fe?
Sunday, October 9, 2016 by sam

Chemistry
Predict the effect of each of the following by mass of water in the hydrate and the chemical of the hydrate? a) not heating the hydrate enough b) overheating the hydrate and producing some copper (ii) oxide C) the initial hydrate appears to weigh less than it actually did, but...
Sunday, October 9, 2016 by Eva

Chemistry
a sample of an ionic compound is dissolved in water and the water gets colder. what is acting as the system?what is acting as the surroundings? does the heat flow from the system to the surroundings or from the surroundings to the system? is this extothermic or endothermic?...
Sunday, October 9, 2016 by Anonymous

Chemistry
a piece of metal is heated by placing it in hot oil. it is removed from the hot oil and placed into a calorimeter of cold water. the water heats up due to the transfer of heat from the metal. what happens to the temperature of the calorimeter? how is the heat that causes the ...
Sunday, October 9, 2016 by Anonymous

Chemistry
Write equations for the dissociation of the following in water. Do not include states in your answer. 1) sodium acetate (NaC2H3O2) NaC2H3O2 ---> Na+ + (C2H3O2)- 2) copper(II) perchlorate Cu(ClO4)2 ---> Cu2+ + 2(ClO4)- Enter balanced ionic and net ionic equations for ...
Sunday, October 9, 2016 by T

Chemistry
Calculate ΔHrxn for the following reaction: CaO(s)+CO2(g)→CaCO3(s) Use the following reactions and given ΔH′s. Ca(s)+CO2(g)+12O2(g)→CaCO3(s), ΔH= -812.8 kJ 2Ca(s)+O2(g)→2CaO(s), ΔH= -1269.8 kJ
Sunday, October 9, 2016 by Hema

chemistry
explain the meaning of this statement"specific heat capicity of alumminium is 900J/kg°C"
Sunday, October 9, 2016 by Riz

chemistry
Lewis sit structure of CH3OH
Sunday, October 9, 2016 by sarfaraj

Chemistry
How do you do significant figures. How dobyou do dimensional analysis
Sunday, October 9, 2016 by Anonymous

Chemistry
The atomic mass of CU 63 is 62.9296 amu with a natural abudance of 0.692. The average mass of copper is 63.546amu.What is the mass of copper's other isotope?
Sunday, October 9, 2016 by Charles

chemistry
when 2g of a gas A is introduced into an evacuated flask kept at 25 centigrade, the pressure is found to be 1 atmosphere.if 3g of another gas is then added to the same flask, the total pressure becomes 1.5atm. assuming ideal behaviour, the ratio of their molecular weights is
Sunday, October 9, 2016 by anjali

chemistry
at 127 centigrade and 1 atm pressure of a gas contains 0.3mole of nitrogen molecule, 0.2 mole of oxygen molecule.the volume of the mixture is
Sunday, October 9, 2016 by Anonymous

Chemistry
24.5 g of H2SO4 (98 g/mol) is added with h20 to make up to 800 ml of a solution. If 50 ml of the H2SO4 is added with 100 ml of H20, what will be the molarity of the diluted solution? MaVa=MbVb (0.3125)(50)=(Mb)(100) Mb= 0.16 M No huh?
Sunday, October 9, 2016 by Joey

Chemistry
Among the following electrons, which has highest energy? a. n = 3, l = 2, m = 0, s = + 1/2 b. n = 4, l = 0. m= 0 , s = - 1/2 Ans is A... but how A? Why nOt B?
Sunday, October 9, 2016 by Nabsha

chemistry
complete the equation for the reaction of the soap with magnesium chloride
Sunday, October 9, 2016 by Dela

chemistry
Say some exples for true solutions.
Saturday, October 8, 2016 by sreeja

chemistry
Which one of the following complex ions has an optical isomer? a. [Zn(phen)2]2+ b. [Cu(CN)4]2– c. [Co(H2O)4en]2+ d. [Zn(NH3)2en]2+ e. [Ni(en)3]2+ how would i go about finding this answer? i don't need the answer give would prefer steps. thanks
Saturday, October 8, 2016 by chem

Chemistry
In a constant-pressure calorimeter, 65.0 mL of 0.320 M Ba(OH)2 was added to 65.0 mL of 0.640 M HCl. The reaction caused the temperature of the solution to rise from 21.98 °C to 26.34 °C. If the solution has the same density and specific heat as water (1.00 g/mL and 4.184 J/g...
Saturday, October 8, 2016 by Bart

Chemistry
A hot lump of 25.6 g of aluminum at an initial temperature of 57.4 °C is placed in 50.0 mL of H2O initially at 25.0 °C and allowed to reach thermal equilibrium. What is the final temperature of the aluminum and water given that the specific heat of aluminum is 0.903 J/(g·°...
Saturday, October 8, 2016 by Bart

Chemistry
Al3+ and HPO42
Saturday, October 8, 2016 by Anonymous

chemistry
What mass of iodine would react with 48 grams of magnesium to make magnesium iodide?
Saturday, October 8, 2016 by juliana

Chemistry
I have a question about solubility rules and net ionic equations so for example : CuSO4+Ba(NO3)2----->BaSO4+Cu(NO3)2 Okay so I know BaSO4 is insoluble while Cu(NO3)is solulable, that means BaSO4 will have a precipitate while Cu(NO3) doesn't. So does that mean the overall ...
Saturday, October 8, 2016 by molly

Chemistry
Why does the element calcium react with water differently than magnesium, potassium and sodium, in a way that calcium looks opaque and cloudy in water and when phenlotphtahein is added it looks bright pink but how come the other elements don't look like that in water? what ...
Saturday, October 8, 2016 by Zyra

physical chemistry
Calculate molarity of air having malar mass 28.8cotaining N2 and O2 only at 273kelvin and 1atm pressure
Saturday, October 8, 2016 by spriha

Chemistry
What are the names of the reactants in this equation? Mg (s) + 2HCl (aq) --> MgCl2 (aq) +H2 (g)
Saturday, October 8, 2016 by Kirsty

Chemistry
Why alkali metals known as alkali metals?
Saturday, October 8, 2016 by Tamax

Chemistry
Complete and balance the following equation. If no reaction occurs, write noreaction . NaOH(aq)+FeBr3(aq)→
Saturday, October 8, 2016 by Sue

Chemistry
sorry i will rephrase the question. what is the chemistry behind these elements to give them these qualities and make them react the way they do with like water and such. 1)magnesium 2)calcium 3)potassium 4)sodium
Friday, October 7, 2016 by Holfbrincl

MS. SUE HELP- Chemistry
Check answers? 1) Why did J.J. Thomson reason that electrons must be a part of the atoms of all elements? A) Cathode rays are negatively charged particles**** B) Cathode rays can be deflected by magnets C) An electron is 2000 times lighter than a hydrogen atom D) Charge-to-...
Friday, October 7, 2016 by Mary

Chemistry
What is happening on a chemical basis, to make them the way they're. 1) magnesium 2)calcium 3)potassium 4)sodium
Friday, October 7, 2016 by Holfbrincl

Organic Chemistry
How many constitutional isomers have the molecular formula C3H6S ?
Friday, October 7, 2016 by Nevaeh

Chemistry
H3C6H5O7(aq) + 3NaHCO3(aq)----Na3C6H5O7(aq) + 3H2O(i) + 3CO2. NaHCO3 = 2.00g H3C6H5O7 = 0.76 CO2 = 0.07g 1.Determine which reactant is the limiting reactant . describe your reasoning. 2. Calculate the theoretical yield of carbon dioxide in the plastic 3. what is the actual ...
Friday, October 7, 2016 by Zaza

chemistry
How many grams silver (Ag) is added to 13 grams gold to produce 85% gold (Au) alloy? Can someone please give me the derived formula to be used? I had managed to solve it though I'm not quite sure if it's correct. i got 73.67g Ag, can someone please correct me if i'm wrong. ...
Friday, October 7, 2016 by Epinephrine

chemistry
Molten Al2O3 is reduced by electrolysis at low potentials and high currents. If 1.5 x 10^4 amperes of current is passed through molten Al2O3 for 8.0 hours, what mass of Al is produced? Assume 100% current efficiency? Mdep = ([1.5 x 10^ x 28800s ]/ 96500) x (26.98/6e) = 20130g ...
Friday, October 7, 2016 by jess

Chemistry
Check answers? 1) Why did J.J. Thomson reason that electrons must be a part of the atoms of all elements? A) Cathode rays are negatively charged particles**** B) Cathode rays can be deflected by magnets C) An electron is 2000 times lighter than a hydrogen atom D) Charge-to-...
Friday, October 7, 2016 by Mary

Chemistry
calculate the energy needed to warm the melted ice from 0 degrees celsius to the final temperature of the water
Thursday, October 6, 2016 by rosa

chemistry
A 100-watt light bulb radiates energy at a rate of 100 J/s. (The watt, a unit of power or energy over time, is defined as 1 J/s.) If all of the light emitted has a wavelength of 525 nm , how many photons are emitted per second? okay so i do: ((6.626*10^-34)(3.00*10^3))/(5.25*...
Thursday, October 6, 2016 by anon yo

Chemistry
Calcium chloride, CaCl2, is used in “hot packs”. When the solid is mixed with water, the products are favored. Based on this information, which of the following is true for the values of ΔH and ΔS for the dissolving process? CaCl2 (s) → Ca2+ (aq) + 2 Cl&#...
Thursday, October 6, 2016 by Bear

Chemistry
Ammonium nitrate, NH4NO3, is used in “cold packs”. Which statement best describes why the products are favored, when the solid is mixed with water? NH4NO3(s) → NH4+ (aq) + NO3- (aq) A) Heat is transferred to the surroundings to lower the temperature and the entropy ...
Thursday, October 6, 2016 by Bear

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