What mass of chlorine is needed to make 117 grams of sodium chloride

Two friends at different locations want to communicate with each other by sending low energy signals. which of the following methods can they use to communicate? a) produce x-rays using colliding electrons and send them to radios, which capture sound b) send messages using infrared radiation, which travel in the form of waves c) send radio waves through intervening media like radio and television d) produce sound waves using microwaves from heated objects

What produces wave a)sound b) heats c)transfer of energy d)vibrations

Magnesium is the limiting reactant in this experiment. calculate the theoretical yield of mgo for each trial. trial 1: trial 2: data mass of empty crucible with lid trial 1: 26.688 trial 2: 26.681 mass of mg metal, crucible, and lid trial 1: 26.994 trial: 2 26.985 mass of mgo, crucible, and lid trial 1: 27.188 trial 2: 27.180