What is the molar mass of al^2(so^4)3

When the water vapor cools it condenses select a number that represents his process on the

Cucl2 + 2nano3 cu(no3)2 + 2nacl what is the percent yield of nacl if 31.0 g of cucl2 reacts with excess nano3 to produce 21.2 g of nacl? 49.7% 58.4% 63.6% 78.7%

What does the symbol (–hfus) indicate in a phase change?