Chemistry - October 2007

Calculate the work done (in Joules) when 45.6 g of tin dissolves in excess acid at 1.03 atm and 23deg.C. Assume ideal gas behavoir

Sn(s) + 2H(+)(aq) ---> Sn(2+)(aq) + H2

2007-10-07 05:20:02 · 1 answers · asked by Anonymous

is it a
solid
liquid
gas
please explain your answer
_x_X_x

2007-10-07 05:17:17 · 19 answers · asked by Anonymous

Calculate the pH of the solution by mixing 40.0 mL of 0.075M BHCl with 60.0mL of 0.050M B.

2007-10-07 04:59:32 · 1 answers · asked by ? 1

which separation method would you use to separate a mixture of lead and aluminum pellets?

2007-10-07 03:42:57 · 4 answers · asked by angela a 1

The number of atoms in a mole is x. How many atoms are contained in
Q1) 4 moles of carbon atoms;
Q2) 8g of oxygen?

2007-10-07 03:12:37 · 2 answers · asked by axb 1

2007-10-07 03:03:21 · 2 answers · asked by Anonymous

Calculate the concentraiton HPO4^2- ions.

2007-10-07 02:23:09 · 1 answers · asked by Physicskid 1

2007-10-07 01:27:26 · 4 answers · asked by kenny 1

If we undergo a reaction that can produce oxygen, and we collect the oxygen in a gas jar. How do we know if we have collected a full gas jar of oxygen? I don't know/

As pure oxygen must be got, we could not use a syringe.

If the gas is chlorine, we can put a pH paper near the open of the gas jar until the pH paper turns red and then white. But how about oxygen?

2007-10-07 01:22:13 · 2 answers · asked by Anonymous

what would they use to neutralise the acid and why. what are 5 characteristic properties of acids and the formulae of the chemical used to neutralise the acid. a word equation for neutralisation reaction. Indicators for strengths of acid. A balanced symbol equation for the neutralisation reaction. The formulae of acids and alkalis.

This is my 11 year old sons chemistry homework. Its got to be presented as a newspaper article - HELP!!!!!!

2007-10-07 00:58:33 · 6 answers · asked by Anonymous

Dear person, in my chemistry textbook it is written that when iron is dipped in concentrated nitric acid, then iron is rendered passive due to the formation of an oxide coating on it; MY qs. is
1) what is the name and formula of that iron oxide.
2) Will nitric acid render all metals passive like iron by forming an oxide layer over it. If no,then what is the reason?
... thanks , swati

2007-10-07 00:15:11 · 1 answers · asked by Anonymous

Or aluminium and lead oxide? Or magnesium oxide and gold?

2007-10-06 23:51:17 · 2 answers · asked by Anonymous

I have read in a book its given the boiling point of nitrogen is -195.8 C

2007-10-06 22:10:48 · 8 answers · asked by chaithra 2

2007-10-06 21:01:44 · 4 answers · asked by mayankkkkk_cancer 1

I'm looking for major companies that use the Draize eye test on rabbits. If anyone knows websites where I can find this information, direction would be appreciated. Thanks :)

2007-10-06 20:48:05 · 1 answers · asked by veggie_fta 2

Because we did flaming testing in the Lab.

2007-10-06 20:13:41 · 3 answers · asked by carpe_diem 1

I recently learned that when crystallizing something such as sulfanilamide, adding too much solvent (such as ethanol) results in little to no yield of purified crystals. Why does this occur?

2007-10-06 20:03:32 · 2 answers · asked by Heather Leigh 1

Okay so i wrote the balanced equation, and thats pretty much all i can do.. if someone can help me that would be so great.. thanks !

CH3C6H13(l) + O2(g) --> 5CO2(g) + 8H2O(l)

Write a balanced equation for the combustion of CH3C6H13(l) (methyl hexane)
-- i.e. its reaction with O2(g) forming the products CO2(g) and H2O(l).

Given the following standard heats of formation:

* deltaHf° of CO2(g) is -393.5 kJ/mol
* deltaHf° of H2O(l) is -286 kJ/mol
* deltaHf° of CH3C6H13(l) is -173.0 kJ/mol


What is the standard heat of reaction (deltaH°) for the combustion reaction of CH3C6H13(l)?

The next question is

Calculate the difference, deltaH-deltaE=delta(PV) for the combustion reaction of 1 mole of methyl hexane.
(Assume standard state conditions and 298 K for all reactants and products.)

2007-10-06 19:13:43 · 1 answers · asked by Anonymous

help! ;)<3

2007-10-06 19:12:07 · 3 answers · asked by Anonymous

You have a large glass flask containing a small amount of acetone (boiling point = 56°C; freezing point = −95°C). The temperature of the flask is that of freezing water. What is the state of acetone in the flask?

2007-10-06 19:07:39 · 6 answers · asked by April 1

2007-10-06 19:00:57 · 2 answers · asked by Booyah! 3

2007-10-06 18:54:42 · 1 answers · asked by decemberkitty02 3

2007-10-06 18:49:47 · 8 answers · asked by Anonymous

2007-10-06 17:09:01 · 13 answers · asked by Somewhere in Time 3

2007-10-06 16:27:08 · 1 answers · asked by andigbf 1

Is it due a to an increase in percentage of chlorine?
Please explain your answer.
Thank You!

2007-10-06 16:07:31 · 1 answers · asked by Anonymous

I have no idea how to solve this problem. I will be honest, yes, this is homework. Any help anyone can give is appreciated!

2007-10-06 16:02:57 · 1 answers · asked by allienoble20 1

2007-10-06 16:01:08 · 3 answers · asked by Em A 1

Express your anwser in calories.

2007-10-06 15:22:04 · 4 answers · asked by Jamie P 1

Does it refer to chemical composition or is it an arbitrary letter-number combination? Or is it something else entirely? Thanks for any insight.

2007-10-06 14:15:33 · 6 answers · asked by Anonymous