I think this is what you wanted, so good luck!
Sr is the limiting reactant.
Given the reaction equation;
2Sr + O2 (g) → 2SrO
2 moles of Sr reacts with 1 mole of O2
2 moles Sr will react with x mole of O2
x = 2 ×1/2
x = 1 mole of O2
Since we have more O2 than required, it is the reactant in excess, hence Sr is the limiting reactant.
Learn more: brainly.com/question/14225536
I believe that the molar mass is 342.34g/mol
The third one down: "When barium hydroxide is mixed with ammonium chloride, ice crystals form on the outside of the container."
This is because an endothermic reaction [process] takes in more energy than it releases. Therefore because a decrease in energy leads to a decrease in temperature, the ice crystals forming show that it must be a endothermic reaction [process].
Hope this helps! :)
AJ
Grow into a cell I think.
