How do you know, when writing a balanced formula, that your reactant or product is a liquid, gas or solid?

Question

I want to know exactly how we would identify the reactants or products in a balanced equation and determine their phases.

Answer 1

Unfortuneately, there is no simple answer to that. Many times the answer is obvious. For example, if H2 is one of the products it is reasonable to assume that it is a gas. Same with CO2 or O2, etc.

Similarly, if you have a replacement reaction and you generate silver or some other metal, it is reasonable to assume that it is a solid.

Otherwise, there is no guarantee. It really depends on the temperaure

Answer 2

the arrow points at the products. H+O---------->H2O. I determine the phases from memory. or i just google the thing in question. Hydrogen and oxygen are easy because they are always gas and when they they are not gas then the problem calls them liquid hydrogen or liquid air or liquid oxygen.

Answer 3

You kind of just have to know. You may have to look up some of them. And some may be in solution or precipitate out.