Question

How much heat is needed to raise the temperature of 7g of water by 18oC?

Answer 1

Answer : Heat, Q = 526.68 J

Explanation :

Given that,

The mass of water, m = 7 g

Change in temperature, $\Delta T=18\ ^0C$

Heat required to raise the temperature is given by :

$Q=mc\Delta T$

Where,

c is the specific heat of the water

For water, $c=4.18\ J/g\ ^0C$

So, $Q=7\ g\times 4.18\ J/g\ ^0C\times 18^0C$

$Q=526.68\ J$

So, heat needed to raise the temperature of 7g of water by $18\ ^0C$ is 526.68 J

Hence, this is the required solution.

Answer 2

Specific heat of water, C = 4.18 J/g. °C
From question, Mass of water= 7g
Temperature difference = 180 degree Celsius

We know by formula,
Heat (Q)= c* m(mass) * T (change in temperature)
 So, Q= 4.18 J/g. °C *7g * 180 °C
         =5266.8 J