How many kJ are equal to 1478 cal?

• A. 6.18 kJ
• B. 3.53 kJ
• C. 0.354 kJ
• D. 147.8 kJ

Answer: (A)

Verified step by step guidance

1. Identify the conversion factor between calories and joules. The relationship is 1 calorie (cal) = 4.184 joules (J).
2. Convert the given energy from calories to joules by multiplying the number of calories by the conversion factor: \$1478 \text{ cal} \times 4.184 \frac{\text{J}}{\text{cal}}$.
3. Calculate the energy in joules (J) from the multiplication in the previous step (do not finalize the number here, just set up the expression).
4. Convert joules to kilojoules (kJ) by dividing the energy in joules by 1000, since 1 kJ = 1000 J: \(\frac{\text{energy in J}}{1000}\).
5. Express the final answer as the energy in kilojoules, which corresponds to the original calories converted to kJ.