What is the molar mass of water (H₂O)?

How many moles are in 44 grams of CO₂? (Molar mass of CO₂ = 44 g/mol)

In a reaction where 3 moles of A react with 2 moles of B to produce 4 moles of C, if you start with 6 moles of A, how many moles of C can be produced?

If a gas has a pressure of 2 atm, a volume of 10 L, and a temperature of 300 K, what is the number of moles of the gas? (R = 0.0821 L·atm/mol·K)