. 4Al + 3O2 → 2Al2 O3 In this reaction, how many moles of O2 are required to completely react with 200 grams of Al? The molar mass of Al is
27 g/mol.
A. 4050 mol O2
B. 5.55 mol O2
C. 7.41 mol O2
D. 9.88 mol O2

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.