Question

The heat required to raise the temperature of 12g of water from 16 C to 21 C is:

Answer 1

Answer:

The heat required to raise the temperature of 12g of water from 16 C to 21 C is 60 cal.

Explanation:

Calorimetry is the measurement and calculation of the amounts of heat exchanged by a body or a system.

There is a direct proportional relationship between heat and temperature. The constant of proportionality depends on the substance that constitutes the body as on its mass, and is the product of the specific heat by the mass of the body. So, the equation that allows calculating heat exchanges is:

Q = c * m * ΔT

where Q is the heat exchanged by a body of mass m, made up of a specific heat substance c and where ΔT is the temperature variation.

In this case, you know:

• Q=?
• c= 4.186 $\frac{J}{g*C}$
• m= 12 g
• ΔT=Tfinal - Tinitial= 21 °C - 16°C= 5 °C

Replacing:

Q= 4.186 $\frac{J}{g*C}$ *12 g *5 °C

Solving:

Q=251.16 J

Since 1 J is equal to 0.2388 cal, then the following rule of three can be applied: if 1 J is equal to 0.2388 cal, then 251.16 J to how many cal are?

$cal=\frac{251.16 J * 0.2388 cal}{1 J}$

cal= 59.98 ≅ 60

The heat required to raise the temperature of 12g of water from 16 C to 21 C is 60 cal.