PLEASE HELP ME PLEASE IM BEGGING

How would the number of moles (n) of o2 change if the atmospheric pressure doubled but all other variables stayed the same

Reacting masses1 calcium carbonate breaks down on heating to produce calcium oxide and carbondioxide gas. caco3 + cao + co2a student heats 15 g of calcium carbonate strongly in a crucible. relative atomic masses (a): ca = 40, c = 12, o = 16.calculate the mass of calcium oxide produced by this reaction.(5 marks)

Sandy is building a small toy car. he wants to use a balloon to power the toy car. he fills a balloon with air and then attaches a straw to the balloon. he tapes the balloon-straw combination to the car and then releases the end of the balloon. the toy moves forward as the air from the balloon comes out the back of the straw. what can sandy do to make the toy car move faster? a) use less air in the balloon. b) blow up the balloon more. c) use a longer straw. d) use larger tires.