For example, when a question asks about two equivalents of bromine, does that mean Br2 OR 2Br2?
Thanks
Strictly speaking, I think that means 2Br2 but I need the equation to tell for sure. Often that refers to Br. For example, if we are talking about the equation of
Cl2 + 2Br- ==> 2Cl^- + Br2 we SHOULD say two equivalents of bromide ion but I often hear two equivalents bromine. The latter is not right.
When a question asks for two equivalents of bromine, it means 2 Br2, not 2Br2.
Here's an explanation of how to determine this:
The term "equivalent" refers to the amount of a substance that can react with, or replace, one mole of hydrogen atoms in a chemical reaction. It's a concept often used in stoichiometry, which is the calculation of relative quantities of reactants and products in chemical reactions.
In the case of bromine, its chemical formula is Br2, meaning it exists as a diatomic molecule. To calculate the number of equivalents, you need to consider the stoichiometry of the reaction.
Since each Br2 molecule contains two moles of bromine atoms (2Br), one equivalent of bromine is equal to one mole of bromine atoms or half a mole of Br2.
Therefore, when a question asks for two equivalents of bromine, it implies two times the stoichiometric amount of bromine, which is 2 x 0.5 mol Br2 = 1 mol Br2, or simply 2 Br2.
Hope this clears up any confusion!