Question

Chalk is made of calcium carbonate. How many moles of chalk do you use when you write your name?

Answer 1

Answer:

Determine mass of chalk stick before writing name

Determine mass of chalk stick after writing name.

Calculate mass of chalk used . Assume this is 0.20g

Molar mass CaCO3 = 100g/mol

Mol CaCO3 in 0.2g = 0.2g/100g/mol = 0.002 mol CaCO3

1 mol CaCO3 molecules= 6.02*10^23 molecules

0.002 mol CaCO3 = 0.002mol *(6.02*10^23) molecules/mol = 1.204*10^21 molecules

1molecule CaCO3 contains 1 C atom

Therefore you have 1.2*10^21 C atoms in your signature.