Question

1. gold has a specific heat of 0.129 j/(g*°c). how many joules of heat energy are required to raise the temperature of 15 grams of gold from 22 °c to 85 °c?

endothermic or exothermic?

Explanation:

Step1: Calculate the temperature change

The formula for temperature change is $\Delta T=T_{final}-T_{initial}$.
Given $T_{initial} = 22^{\circ}C$ and $T_{final}=85^{\circ}C$, so $\Delta T=85 - 22=63^{\circ}C$.

Step2: Use the heat - transfer formula

The heat - transfer formula is $Q = mc\Delta T$, where $m$ is the mass, $c$ is the specific heat capacity, and $\Delta T$ is the temperature change.
Given $m = 15g$, $c=0.129J/(g\cdot^{\circ}C)$, and $\Delta T = 63^{\circ}C$.
Substitute the values into the formula: $Q=(15g)\times(0.129J/(g\cdot^{\circ}C))\times(63^{\circ}C)$.
First, calculate $15\times0.129 = 1.935$.
Then, $1.935\times63=121.905J$.

Since heat is absorbed (temperature is rising), the process is endothermic.

Answer:

The amount of heat energy required is $121.905J$ and the process is endothermic.