Question

the energy produced by a snack in an experiment is calculated to be 1,254 j/g. what is the energy of the snack in calories/gram? 1000 cal = 1 cal 1,254 (j/g) = ? (cal/g) remember there are 4.18 joules per 1 calorie.

Explanation:

Step1: Convert J to cal

Use the conversion factor \( 1\ \text{cal} = 4.18\ \text{J} \). So, \( 1254\ \frac{\text{J}}{\text{g}} \times \frac{1\ \text{cal}}{4.18\ \text{J}} \).

$$ 1254\div4.18 \approx 299.999\ \frac{\text{cal}}{\text{g}} $$

Step2: Convert cal to Cal

Use the conversion factor \( 1\ \text{Cal} = 1000\ \text{cal} \). So, \( 299.999\ \frac{\text{cal}}{\text{g}} \times \frac{1\ \text{Cal}}{1000\ \text{cal}} \).

$$ 299.999\div1000 \approx 0.3\ \frac{\text{Cal}}{\text{g}} $$

(or more precisely, \( \approx 0.299999 \approx 0.3 \))

Answer:

\( 0.3 \) (or more accurately, approximately \( 0.299 \) to \( 0.3 \))