Which sample contains the greatest total number of atoms?
12.0 g of CH412.0\text{ g of } \text{CH}_412.0 g of CH4
35.0 g of NH335.0\text{ g of } \text{NH}_335.0 g of NH3
99.0 g of CO299.0\text{ g of } \text{CO}_299.0 g of CO2
115.0 g of CO115.0\text{ g of } \text{CO}115.0 g of CO