chem question...?

Question

1. The percentage by mass of hydrogen in calcium dihydrogenphosphate is given approximately by:

a) (1*2*100)/((40) + 2(1 + 31 + 64))

b) (1*2*2*100)/((40) + (4y1) + (2*31) + (8*16))

c) (1*2*2*100)/((12) + (4*1) + (2*31) + (8*16))

d) (1*2*100)/((40) + 2(2+ 31 +64))

e) (1*2*100)/((40) + (2*1) + 31 + 64

2. Which of the following is highest in mass?
a) 15.0 moles of helium, He
b) 5.0 moles of carbon, C
c) 2.0 moles of nitrogen monoxide, NO
d) 0.50 moles of yellow phosphorous, P4
e) 1.50moles of sodium hydroxide, NaOH

Thanks for helping me. For the 1st question I put a set of brackets for the whole numerator and a set of brackets for the denominators of the fractions. / means divide by. Thanks so much!

Answer 1

1. Calcium dihydrogenphosphate is Ca(H2PO4)2, so the correct answer is D (MW of calcium dihydrogen phosphate would be 40 + 2(2 + 31 + 64)).
2. a) 15 moles of He weighs 60 g. b) 5 moles of C weighs 60 grams. c) 2 moles of NO weighs 60 g. d) 0.50 moles of P4 weighs 62 grams. e) 1.5 moles of NaOH weighs 60 grams. Correct answer is D.

Answer 2

for Q 2,
you got close to 60g if u calculate a,b,c,e
if u have to choose the highest, choose c , it is 60.2g

Answer 3

wtf is that????