Question

`H_2(g) + Cl_2(g) rarr 2HCl(g)` The give reaction occurs at constant pressure...which is the only viable observation?

`"1. Pressure will increase in reaction."`
`"2. Mass will increase in reaction."`
`"3. Pressure will decrease in reaction."`
`"4. Mass is conserved in the reaction."`

Answer 1

`"Option 4"` is the only viable answer.

Explanation:

YOu have been given the chemical equation:

`H_2(g) + Cl_2(g) rarr 2HCl(g)`

There are 2 equiv (moles if you like) of gaseous product, and 2 equiv gaseous reactant. Clearly, mass is conserved in a chemical reaction, as are pressure and volume in this scenario, because temperature was specified to be constant. `"Option 4"` is the only starter.