Question

How much heat is needed to raise the temperature of 7g of water by 19oC?

Answer 1

Data:

m = 7 g

ΔT = 19 °C

Cs of water = 1 cal / g °C

Formula Q = m * Cs * ΔT

Solution:

Q = (7 g) * (1 cal / g °C) * ( 19°C) = 133 cal

Answer 2

Answer: The heat required is 556.738 Joules.

Explanation:

To calculate the heat required, we use the equation:

$Q= m\times c\times \Delta T$

where,

Q = heat absorbed = ? Joules

m = mass of water = 7g

c = heat capacity of water = 4.186 J/g ° C      

$\Delta T=\text{Change in temperature}=19^oC$ 

Putting values in above equation, we get:

$Q=7g\times 4.186J/g^oC\times 19^oC$

Q = 556.738 J

Hence, the heat required by water is 556.738 Joules.