Why might the amount of copper produced be less than 100% of the expected amount? check all possible reasons.

there are impurities in the substances.

the reaction might not go to completion.

the amount of one of the reactants might be measured incorrectly.

the molar ratio may not be correct.

the expected amount might be based on measurements with error

There are impurities in the substances.
The reaction might not go to completion.
The amount of one of the reactants might be measured incorrectly.
The expected amount might be based on measurements with error.

Answer;There are impurities in the substances.The reaction might not go to completion.The amount of one of the reactants might be measured incorrectly.The expected amount might be based on measurements with errorExplanation;Yield is the amount of product obtained from a chemical reaction. Percentage yield serves as a measure of the effectiveness of a chemical synthetic procedure. It is calculated by dividing the amount of the actual yield obtained by the theoretical yield.Percentage yield may be less than 100 percent due to a number of reasons which includes; presence of impurities that do not react, the reaction being incomplete and thus reactants are not completely converted to products, amount of one of reactants may be measured incorrectly, etc.

Because a model would make the investigation easier to understand

It was ernest rutherford