Question

Concrete has a specific heat capacity of 3.3 J/(g *oC). How much energy is necessary to heat up 2,000 g of concrete from 25oC to 55oC?

Answer 1

`\boxed {\boxed {\sf 198,000 \ Joules}}`

Step-by-step explanation:

We want to find energy and we are given the specific heat capacity, mass, and change in temperature. We must use this formula:

`q=mc \Delta T`

where m is mass, c is the heat capacity, and ΔT is the change in temperature.

We know the mass is 2,000 grams, the heat capacity is 3.3 J/g °C.

To find the change in temperature, subtract the final temperature and initial temperature.

• ΔT= final temp. - initial temp.
• ΔT= 55°C -25°C
• ΔT= 30°C

Substitute the known values into the formula.

`q= (2000 \ g)( 3.3 \ J /g \textdegree C) (30 \textdegree C)`

Multiply the first two numbers and note the grams will cancel out.

`q= (6600 \ J/ \textdegree C)( 30 \textdegree C)`

Multiply again. This time, the degrees Celsius will cancel.

`q= 198000 \ J`

198,000 Joules of energy are required.