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irina [24]
3 years ago
5

A chemical reaction requires 31.39 kJ. How many kilocalories does this correspond to?

Chemistry
1 answer:
Allushta [10]3 years ago
3 0
<h3>Answer:</h3>

7.502 kilo calories

<h3>Explanation:</h3>

<u>We are given;</u>

  • Quantity of heat, Q as 31.39 kJ

We are required to convert it to kilo calories

First, we convert it to Joules

1 kJ = 1000 J

Therefore;

31.39 kJ will be equivalent to 31390 Joules

Second we convert Joules to calories using a suitable conversion factor

The suitable conversion factor is 4.184 J/Cal

Thus;

31390 Joules will be equivalent to;

= 31390 J ÷ 4.184 J/Cal

= 7502.39 Cal

Third, we convert calories to kilo calories

1 kCal = 1000 cal

Therefore;

7502. 39 Cal will be equivalent to;

= 7502.39 ÷ 1000

= 7.50239

=7.502 kilo calories

Hence, 31.39 kJ will correspond to 7.502 kilo calories

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Answer:

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