How many moleules of SiO2 would be needed to have a mass of 12.40 grams

What is the mass of sodium in 3 moles of sodium chloride

The boiling point of propanoic acid is higher than that of 1-butanol because: propanoic acid has a higher molecular weight than 1-butanol. propanoic acid is more soluble in water than 1-butanol. propanoic acid is a better hydrogen bond donor than 1-butanol. propanoic acid forms hydrogen bonded dimers and 1-butanol does not. 1-butanol forms hydrogen bonded dimers and propanoic acid does not.

What conclusion can you draw from this experiment about the components of the black ink?