Question

DIRECTIONS: A. How many atoms are in each of the following samples?

a.11.3g Pb

b.44.2g Mg

B. Calculate the mass in grams of each of the following samples.

a.1.50x10^18 atoms Ne

b.8.35x10^21molecules CH4

1. What is the percent composition of the following compounds? a.Naphtalene(C10 H8 )

b.Sucrose(C12 H22 O11 )

c.Aluminum sulfate(Al2(SO4)3

Answer 1

A) a) $3.28××10 ^{21}$ Atoms

b) $1.109×10 ^{23}$ Atoms

B) a) 1,200g

b) 8.67g

1.a) Naphtalene(C10 H8 )

C=93.75%,H=6.25%

b) Sucrose(C12 H22 O11 )

C=42.11%,H=6.43%,O=51.46%

c)Aluminum sulfate(Al2(SO4)3

Al=15.79%,S=28.07%,O=56.14%