The temperature of a sample of water changes from 10°C to 20°C when the water absorbs 420 joules of heat. What is the mass of the sample?

1 Answer
Mar 2, 2016

Answer:

#10.03# grams

Explanation:

The problem can be solved using the formula:

#Q=mCpDeltaT#

where:

#Q=heat#
#m=mass#
#Cp=sp. heat#
#DeltaT=temperature# change #(T_2-T_1)#

Some data are provided in the problem like
#Q=420# Joules
#T_2=20^oC#
#T_1=10^oC#
and the ##[specific heat](http://socratic.org/chemistry/thermochemistry/specific-heat) of water is known to be #4.186 (J)/(g.^oC)#. (http://www.calculator.org/property.aspx?name=specific%20heat%20capacity)

All you have to do is to rearrange the original formula to isolate #m# and to derive the new formula which is;

#m=(Q)/(CpDeltaT)#, plug in values and make sure to cancel out units.
until you have the desired unit.