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3 years ago

11

A substance has a specific heat capacity of 2.0 J/g °C. How many joules are needed to raise the temperature of 30.0 g of this su

bstance from 0°C to15°C?
a. 1 J

b. -1 J

c. -900 J

d. 900 J

2 answers:

Vesnalui [34]3 years ago

7 0

Answer:

$\Large \boxed{\sf 900 \ J}$

Explanation:

Use formula

$\displaystyle \sf Energy\ (J)=mass \ (g) \times specific \ heat \ capacity \ (Jg^{-1}\°C^{-1}) \times change \ in \ temperature \ (\°C)$

Substitute the values in formula and evaluate

$\displaystyle \sf Energy\ (J)=30.0\ g \times 2.0 \ Jg^{-1}\°C^{-1} \times (15\°C-0\°C)$

$\displaystyle Q=30.0 \times 2.0 \times (15-0 )=900$

3241004551 [841]3 years ago

5 0

Answer:

g

Explanation:

know what you think about th can get it

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