What is the mass of 0.38 moles of cobalt?

How much heat is released upon converting one mole of steam (18.0 g) from 100.0 ∘c to water at 25.0 ∘c? show work and constants, trying to figure out how it works. only given the heat capacity for steam and water so try to only use that

If 22.5 liters of oxygen reacted with excess of hydrogen, how many liters of water vapor could be produced?

What are the coefficients that will balance the skeleton equation below? n2 + h2 → nh3