How much adding machine tape would be required to construct a model with a scale distance 1Au=2m

Calculate the mass of silver needed to react with chlorine to produce 126g if silver chloride?

The molality of calcium chloride (cacl2) in an aqueous solution is 2.46 m. what is mole fraction of the solute?

A5 mole sample of liquid acetone is converted to a gas at 75.0°c. if 628 j are required to raise the temperature of the liquid to the boiling point, 15.600 kj are required to evaporate the liquid, and 712 j are required to raise the final temperature to 75.0°c, what is the total energy required for the conversion?