Please help me!!! 1. Convert 4mols H20 to grams?

а 72g
b 92g
c 83g
d 62g

2. Convert 4mols of H2O to atoms of H2O?

a 1.4 x 10^24 atoms H2O
b 4.1 x 10^24 atoms H2O
c 3.3 x 10^24 atoms H2O
d 2.4 x 10^24 atoms H2O

Inside a flashbulb, oxygen surrounds a thin coil of magnesium. when the flashbulb is set off, a chemical reaction takes place in which magnesium combines with oxygen to form magnesium oxide. which of the chemical equations matches the reaction above? a. mg + o2 mgo2 + energy b. 2mg + o mg2o + energy c. 2mg + o2 2mgo + energy d. mg + o mgo + energy