To Chemistry experts - I NEED YOUR HELP!!!!!!! - TennisForum.com
Old Dec 18th, 2004, 02:47 AM Thread Starter
Senior Member

Join Date: Mar 2004
Posts: 27,568

To Chemistry experts - I NEED YOUR HELP!!!!!!!

If you know how to do my fucking homework, Help me plzzzz

Write a Chemical equation for 1 & 2:
1 Calcium carbonate solid and dilute nitric acid
2 Zinc carbonate and dilute sulphuric acid

3 5.80 g of a gaseous compound X (containing carbon and hydrogen only) were completely burnt in excess dry oxygen. The products were passed through a suitable drying apparatus containing anhydrous calcium chloride, and it was found that 9.00 g of water had benn formed.
(a) Calculate the mass of hydrogen in 9.00 g of water.
(b) Calculate the mass of carbon in 5.80 of X.
(c) Find the empirical formula of X.

Multiple Choice
4 13.70 g of an oxide of metal X (relative atomic mass = 207.0) reacts with excess hydrogen to produce 1.44 g of water. What is the empirical formula of the oxide?
A. XO
B. XO2
C. X2O
D. X3O4

5 A mixture of magnesium chloride and magnesium sulphate contains 0.6 mole of chloride ions and 0.2 mole of sulphate ions. The number of moles magnesium ions present is
A. 0.4 mol.
B. 0.5 mol.
C. 0.8 mol.
D. 1.0 mol.

Dementia
Serena X Venus
Holy "TF FAVOURITES" Trio- Guestoria X Q.V. Aga X KAMAN Karolina
FormalEducation is offline

Old Dec 18th, 2004, 03:17 AM
Senior Member

Join Date: Sep 2001
Posts: 14,447

have you tried it yourself? you should, cause stoichiometry apparently requires lots of practice
hint: write your stoichiometric equations first
3 is slightly more challenging than the rest, so what you could do is to write the equation of combustion first

CxHy + (y/4 +x) O2 --> y/2 H2O + xCO2

then solve for x and y, since you do know the amount of water produced

A single flow'r he sent me, since we met./All tenderly his messenger he chose;
Deep-hearted, pure, with scented dew still wet - One perfect rose.
I knew the language of the floweret;/'My fragile leaves,' it said, 'his heart enclose.'
Love long has taken for his amulet/One perfect rose.
Why is it no one ever sent me yet/One perfect limousine, do you suppose?
Ah no, it's always just my luck to get/One perfect rose.
moby is offline
Old Dec 18th, 2004, 03:18 AM
Senior Member

Join Date: Mar 2003
Posts: 377

Quote:
Originally Posted by E.Dementieva
If you know how to do my fucking homework, Help me plzzzz

Write a Chemical equation for 1 & 2:
1 Calcium carbonate solid and dilute nitric acid
2 Zinc carbonate and dilute sulphuric acid
CaCO3 + 2HNO3 = Ca(NO3)2 + H20 + C02

ZnCO3 + H2SO4 = ZnSO4 + CO2 + H20

Their both carbonate reactions carbonate + acid = Metal + C02 + Water etc

I can do the other ones but dont have time, so good luck.
Cuckoo is offline
Old Dec 18th, 2004, 07:48 AM Thread Starter
Senior Member

Join Date: Mar 2004
Posts: 27,568

thx folks

infact i know carbonate + acid = Metal + C02 + H2O,
i just dun no how to balance the equation

Dementia
Serena X Venus
Holy "TF FAVOURITES" Trio- Guestoria X Q.V. Aga X KAMAN Karolina
FormalEducation is offline
Old Dec 18th, 2004, 08:04 AM
Senior Member

Join Date: Mar 2003
Posts: 377

oh thats simple, i can teach u if u want.
Cuckoo is offline
Old Dec 18th, 2004, 09:22 AM
Senior Member

Join Date: Jan 2003
Posts: 24,486

I can't be bothered to do all the calculations You can work out the balanced equation from oxidation numbers, that's how I find easier to do

So this is love, Mmmmmm
So this is love
So this is what makes life divine
I'm all aglow, Mmmmmm
And now I know
The key to all heaven is mine
My heart has wings, Mmmmmm
And I can fly
I'll touch every star in the sky
So this is the miracle that I've been dreaming of
Mmmmmm
Mmmmmm
So this is love

A dream is a wish your heart makes when you're fast asleep, in dreams you lose your heartaches, whatever you wish for, you keep

Ting is offline

Message:
Options

## Register Now

In order to be able to post messages on the TennisForum.com forums, you must first register.

User Name:
OR

## Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.