Which salt is the best choice for a hot pack? Why? and Which salt is the best choice for a cold pack? Why? is it sodium chloride, lithium chloride, sodium hydroxide, or potassium chloride?

thermochemistry

The density of an unknown gas at 98°c and 740 mmhg is 2.50 g/l. what is the molar mass of the gas with work showed?

1.aluminum chloride (alcl3), and sodium hydroxide (naoh) can react to form aluminum hydroxide (al(oh)3) and sodium chloride (nacl).    you have 13.4 g of aluminum chloride and 10.0 g of sodium hydroxide. answer the following questions: •what is the balanced equation for this reaction? •if you use all 13.4 g of aluminum chloride, how many grams of aluminum hydroxide can be formed? work must be shown to earn credit •if you use all 10.0 g of sodium hydroxide, how many grams of aluminum hydroxide can be formed? work must be shown to earn credit •how many grams of aluminum hydroxide will actually be made?     which reagent is limiting? explain your answer.

Answer explain why it is not possible to deduce a complete order of reactivity.