To completely dissolve 2.4g of a metal oxide with valence 2, it is necessary to use just enough 10g of 21.9% HCl solution. Which metal oxide is it?​

What three things does a balanced equation show you?

Butane gas reacts with oxygen gas to give carbon dioxide gas and water vapor (gas). if you mix butane and oxygen in the correct stoichiometric ratio, and if the total pressure of the mixture is 390 mmhg, what is the pressure (in mmhg) of water vapor after the reaction is completed (temperature and volume do not change).

You have a sample of a metal, the sample is exactly 6.02 x 1023atom, if the sample has a mass 55.85 what metal is your sample made of?