There are two reactants in a chemical equation and one product. The mass of the product is 32g. The mass of the first reactant is 18g. What must the mass of the second reactant be?

Ineed the answers for these promblems i have

Asmall object with mass 0.200 kg swings back and forth on the lower end of a light rope that is 3.00 m long. the upper end of the rope is attached to the ceiling. as the object swings through its lowest position, where the rope is vertical, the speed of the object is 5.80 m/s. at this point in the motion, what is the tension in the rope? (use g = 9.80 m/s2.)

Achlorine atom has 17 protons and 18 neutrons. what is its mass number? what is its atomic number?