Pls answer these and show work

Acetylene gas c2h2 undergoes combustion to produce carbon dioxide and water vapor how many grams of water are produced by the same amount of c2h2?

The density of the solid phase of a substance is 0.90 g/cm3 and the density of the liquid phase is 1.0 g/cm3. a large increase in pressure will a. lower the freezing point b. raise the freezing point c. lower the boiling point d. raise the triple point e. lower the triple point

Analyze the reaction to determine whether the reaction is exothermic or endothermic. explain your reasoning.