# AP Chemistry

posted by .

(a)calculate the mass percent of carbon in the hydrated form of the solid that has the formula BeC2O4 X 3 H2O (s).

I divided 24.02 g by 151.08 g and got .16, or 16%. is that correct?

Also, I'm having trouble with this follow up question.

When heated to 220 degrees C, BeC2O4 X 3 H2O dehydrates completely as respresented: BeC2O4 X 3 H2O (s)--> BeC2O4 + 3H20 (g). If 3.21 g of BeC2O4 X 3 H2O is heated to 220 degrees C, calculate the:

(i) mass of BeC2O4 (s) formed
(ii) volume of H2O (g) released, measured at 220 degrees C and 735 mm Hg

• AP Chemistry -

I didn't check the formula weight of the BeC2O4.3H2O for the first, but the procedure is right.

On the second, calculate the percent composition of 3H2O in the BeC2O4.2H2O, then you can do i easily.

for ii, change it to moles, then V= nRT/P

• AP Chemistry -

Yes, the answer comes out to be 15.9%. As for the second part, it is a simple problem.

3.21g BeC2O4 3H2O x (1 mol BeC2O4 3H2O/151.03g) x (1 mol BeC2O4/1 mol BeC2O4) x (97.01/1 mol BeC2O4) = 2.06 g

ii. Since it is measured at STP, we can assume that 22.4 L of the substance = 1 mol.

3 mol H2Ox (22.4 L H2O/1 mol H2O) = 67.2 L H20

• AP Chemistry -

The measurements are not at STP, they are at 220 celsius and 735 mm Hg. so you use PV=nRT in this instance

## Similar Questions

1. ### science

a)Calculate the mass percent of carbon in the hydrated form of the solid that has the formula BeC2O4 loosly bonded to 3H2O. b)When heated to 220degrees C, BeC2O4loosly bonded to 3H2O(s) dehydrates completely as represented below: BeC2O4loosely …
2. ### chemistry

when 1.40 g of hydrated magnesium salfate is heated to constant mass, 0.68 g of the anhydrous salt remains. find the formula for the hydrated magnesium sulfate. MgSO4*xH2O ==> MgSO4 + xH2O grams water = 1.40 - 0.68 = ?
3. ### Chemistry

If 3.21 g of BeC2O4 * 3H2O is heated to 220 C calculate the volume of the H2O(g) released, measured at 220 C and 735 mm Hg?
4. ### chemistry

6.Answer the following questions about BaC2O4 and its hydrate: A. calculate the mass percent of carbon in the hydrated form of the solid that has the fromula BaC2O4 * 3H2O
5. ### chemistry

From the following combustion: 1-butanol + oxygen+ carbon dioxide + water. How many grams of carbon dioxide and water are produced when 130.6 grams of 1-butanol is completely burned?
6. ### chemistry

a hydrated salt is a solid that includes water molecules within its crystal structure. a student heated a 9.10-gram sample of a hydrated salt to a constant mass of 5.41 grams. what percent by mass of water did the salt contain?
7. ### Chem 11

So I did a lab determining the chemical formula of a hydrate. I really just need somebody to check this over for me. We had to find the molecular formula of a hydrate of copper (2) sulphate, CuSO4 .xH2O. My observation table looks …
8. ### Chemistry 11

So I did a lab determining the chemical formula of a hydrate. We had to find the molecular formula of a hydrate of copper (2) sulphate, CuSO4 .xH2O. My observation table looks like this: Mass of clean, dry test tube: 21.6g Mass of …
9. ### chemistry

Determine the percent by mass of water in your sample of hydrated copper (II) sulfate - CuSO4. xH2O My work I got 10% is this correct?
10. ### chemistry

Suppose a substance has been prepared that is composed of carbon, hydrogen, and nitrogen. When 0.1156 gram of this compound is reacted with oxygen, 0.1638 gram of carbon dioxide (CO2) and 0.1676 gram of water (H2O) are collected. Assuming …

More Similar Questions