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* 4.18\ J/g\ ^0C* 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