A breaker holds 124.9 g of water. The initial temperature of the water is 22.3 C how much energy is needed to raise the temperature of the water to 33.5 C? The specific heat of the water is 4.18 j/g* C

Respuesta :

Answer:

Approximately [tex]5.85 \times 10^{3}\; {\rm J}[/tex] assuming no energy loss to the surroundings of the water in this beaker.

Explanation:

Let [tex]c[/tex] denote the specific heat of a material. The energy [tex]Q[/tex] required to raise the temperature of [tex]m[/tex] (mass) of this material by [tex]\Delta T[/tex] (change in temperature) is:

[tex]Q = c\, m\, \Delta T[/tex].

In this question, it is given that the specific heat of water is [tex]c = 4.18\; {\rm J \cdot g^{-1}\cdot K^{-1}}[/tex]. It is also given that the mass of the water in this beaker is [tex]m = 124.9\: {\rm g}[/tex].

The change in the temperature is:

[tex]\Delta T = (33.5 - 22.3)\; {\rm K} = 11.2\; {\rm K}[/tex].

Assume that there is no heat loss to the surroundings of the water in this beaker. Energy required to achieve this change in temperature would be:

[tex]\begin{aligned}Q &= c\, m\, \Delta T \\ &= 4.18 \; {\rm J \cdot g^{-1}\cdot K^{-1}} \times 124.9\; {\rm g} \times (33.5 - 22.3)\; {\rm K} \\ &= 4.18 \; {\rm J \cdot g^{-1}\cdot K^{-1}} \times 124.9\; {\rm g} \times 11.2 \; {\rm K} \\ &\approx 5.85 \times 10^{3}\; {\rm J}\end{aligned}[/tex].