# How much energy in J is lost when a sample of iron with a mass of 27.8 grams cools from 76 to 26...

## Question:

How much energy in J is lost when a sample of iron with a mass of 27.8 grams cools from 76 to 26 degrees Celcius?

## Energy Loss:

In the process of energy transfer of when the energy displaces from one position to another then there is some energy loss. The energy that is lost is known the type of disordered that can't be used to do work.

## Answer and Explanation:

Given Data

• The mass is {eq}m = 27.8\;{\rm{gram}} {/eq}.
• The initial temperature is {eq}{T_1} = 76{\rm{^\circ C}} {/eq}.
• The final temperature is {eq}{T_2} = 26{\rm{^\circ C}} {/eq}.

The expression for the energy lost is,

{eq}Q = m{C_P}\left( {{T_1} - {T_2}} \right) {/eq}

The specific heat for iron is {eq}{C_p} = 0.44\;{\rm{J/g^\circ C}} {/eq}.

Substitute the given values.

{eq}\begin{align*} Q &= \left( {27.8\;{\rm{gram}}} \right)\left( {0.44\;{\rm{J/g^\circ C}}} \right)\left( {76{\rm{^\circ C}} - 26{\rm{^\circ C}}} \right)\\ &= 611.6\,{\rm{J}} \end{align*} {/eq}

Thus, the energy loss is {eq}611.6\,{\rm{J}} {/eq}.

#### Learn more about this topic:

Conserving Energy at Home: How to Be More Energy Efficient

from Geography 101: Human & Cultural Geography

Chapter 13 / Lesson 10
19K