Question

How much heat energy in joules is necessary to raise the temperature of 5kg of water from 20°C to 100°C ??​

Answer 1

Answer:

hope my answer in the above attachment helps

Answer 2

Given:

• How much heat energy in joules is necessary to raise the temperature of 5kg of water from 20°C to 100°C ??

To Find:

• Heat energy required in Joules = ?

Acknowledgement:

• $\sf{m \times c \times \delta \: T}$

Solution:

Change in temperature is given by:

$\\ \longrightarrow\sf{ \delta \times T} \\ \\ \longrightarrow\sf{100 - 20} \\ \\ \longrightarrow\sf{ {80}^{ \circ} }$

Thus, Change in temperature is about 80°C.

We know that,

Energy to be supplied to water = Change in temperature of water.

$\longrightarrow$ Mass of water × specific heat of water × change in temperature of water.

Here,

• $\sf{m = 5kg}$

• $\sf{c = 4.2}$

• $\sf{ \delta \: T = {80}^{ \circ}c }$

Applying in our formula:

$\\ \longrightarrow\sf{5 \times 4.2 \times {80}^{ \circ} } \\ \\ \longrightarrow\sf{21 \times {80}^{ \circ} } \\ \\ \longrightarrow\sf{1680 \: J}$

Hence,

$\therefore$ The heat energy required is 1680 Joules.