# What possible reasons could be advanced that Jim recovered 82*g of product that yielded 95*g?

Nov 16, 2016

Clearly, Jim is a duffer in the lab.

#### Explanation:

In every chemical reaction ever performed, mass is conserved. If you start with $100 \cdot g$ of reactants, at most you can get $100 \cdot g$ of product. In practice you are not even going to get that. Reactions seldom proceed with 100% yield, and even if they do, some losses are going to occur on handling, i.e. getting your product out of the reaction vessel, purifying it, getting it into a tared bottle; mass loss occurs down the line.

Here, Jim lost $\left(95 - 82\right) = 13 \cdot g$. Jim was apparently a bit lax in scraping his product out of the reaction vessel; or maybe it didn't crystallize out of solution completely. If the product were pure, the loss may be acceptable.