Question

What mass of water is required to absorb 4.7 x 10^5 of energy from a car engine while the temperature was initially 25 what will be the new temperature

Answer 1

The mass of water required is, m = 1.492 Kg

The final temperature of water,
`T_(f)` = 100 °C

Step-by-step explanation:

Given that

Energy absorbed by water, q = 4.5 x 10⁵ J

The initial temperature of water
`T_(i)` = 25 °C

The mass of water required to absorb the energy, m = ?

The final temperature of water,
`T_(f)` = ?

The formula for energy absorbed by the water,

q = m C ΔT Joules

where,

C - specific heat capacity (4200 J/Kg °C)

ΔT =
`T_(f)` -
`T_(i)` (change in temperature)

The maximum possible temperature of the water at Standard Temperature and Pressure is 100 °C

As the final temperature is not given, let us consider the maximum possible temperature of the water.

Therefore,

ΔT =
`T_(f)` -
`T_(i)`

= 100 -25

= 75 °C

To find the mass of water, from the above relation

m = q/CΔT Kg

Substituting the values in the above equation

m = 4.5 x 10⁵/4200 x 75

m = 1.492 Kg

Hence, the mass of water required is m = 1.492 Kg