1.a Expressing amounts of energy in different energy units is necessary to solve many chemistry problems. For practice, complete the following table.

The Joule (J) is the SI unit of energy. 1 calorie (cal) = 4.184 J

1.b Expressing amounts of energy in different energy units is necessary to solve many chemistry problems. For practice, complete the following table.

The Joule (J) is the SI unit of energy. 1 calorie (cal) = 4.184 J; 1 kcal = 1000 cal

\begin{tabular}{|c|c|c|} \hline J & cal & kJ \\ \hline 642 & & \\ \hline & & \\ \hline & 138 & \\ \hline & & \\ \hline & & 0.451 \\ \hline \end{tabular} \begin{tabular}{|c|c|c|} \hline J & kJ & kcal \\ \hline 642 & & \\ \hline & 0.736 & \\ \hline & & \\ \hline & & 0.181 \\ \hline \end{tabular}