Multipe choice again...thanks?

Question

1. Calcium carbonate decomposes when heated strongly. The decomposition is represented by the equation
CaCO3(s) -(arrow) CaO(s) + CO2(g)
The mass of calcium oxide produced from 25g of calcium carbonate is about
a) 25g
b) 14g
c) 16g
d) 8g

2. Washing soda crystals have the formula, Na2CO3.10H2O. If 10.0g of the crystals are heated to remove all the water, the mass loss would be
a) 0.50g
b) 0.63g
c) 3.70g
d) 6.29g

Thankyou. Please help chemistry wizzes.

I've done these questions. I am just asking if someone would kindly help by answering these questions so I definitely get these answers correct by having more than one chemistry wizz's opinion (I'm not too confident with a few of the questions). Thankyou.

Answer 1

1.) One mole of CaCO3 will produce one mole of CaO.

25 g / 100.1 g/mole = 0.250 moles of CaCO3

0.250 moles * 56.1 g/mole = 14.0 grams CaO (b)

2.) The ratio of anhydrous salt to hydrate is

(106.0 g/mol)/ (106.0 g/mol + 10*18.02 g/mol)
= 106.0 / (106.0 + 180.2) = 106.0 / 286.2 = 0.370

10 grams would yield 10*0.370 = 3.70 grams (c)

Answer 2

You learn more by doing your own homework. Read the book. Listen in class. Exert the effort. I try to help, but in this case it's too spelled out.