Question

copper metal has a specific heat of 0.385 j/g °c. calculate the amount of heat required to raise the temperature of 22.8 g of copper from 20.0 °c to 875 °c.
1.97 kj
10.5 kj
7.84 kj
3.29 kj
7.51 kj
question 2
2 pts
how much heat is evolved when 320 g of so₂ is burned according to the chemical equation shown below?
2 so₂(g) + o₂(g) → 2 so₃(g) δh° = -198 kj
546 kj
185 kj
371 kj
885 kj
495 kj

Explanation:

Step1: Calculate the temperature change

The formula for temperature change \(\Delta T=T_{final}-T_{initial}\).
Given \(T_{initial} = 20.0^{\circ}C\) and \(T_{final}=875^{\circ}C\), so \(\Delta T=875 - 20.0=855^{\circ}C\)

Step2: Use the heat - transfer formula

The heat - transfer formula is \(q = mc\Delta T\), where \(m = 22.8g\), \(c=0.385J/g^{\circ}C\), and \(\Delta T = 855^{\circ}C\)

Substitute the values into the formula:
\(q=(22.8g)\times(0.385J/g^{\circ}C)\times(855^{\circ}C)\)

First, calculate \(22.8\times0.385 = 8.778\)

Then, \(q=8.778\times855J\)

\(q = 7505.19J\)

Convert joules to kilojoules: \(q=\frac{7505.19J}{1000}=7.50519kJ\approx7.51kJ\)

Answer:

7.51 kJ