A 20.00 g mixture of magnesium and zinc metal reacting with excess hydrochloric acid produced 1.102 g of hydrogen gas. What is the percent zinc in the original mixture?

How many liters of ethylene glycol antifreeze (c2h6o2), with a density of 1.100 g/l, would you add to your car radiator containing 15.0 kg of water if you needed to protect your engine to - 21.5°c? for water, kf = 1.86°c m -1.