Question

The actual density of copper is 8.96
g/cm3.
A lab team measured the density of a copper sample to be 8.40
g/cm3.

Part A: Which expression shows how to calculate the percent error for the measured density of the copper sample?

Part B: What is the percent error?

Select two answers: one for Part A and one for Part B.

Responses

B: 6.25%
B: 6 point 2 5 percent

A: |8.40−8.96|8.96⋅100
A: |8.40−8.96|8.96⋅100

B: 93.75%
B: 93 point 7 5 percent

A: |8.40|8.96⋅100
A: |8.40|8.96⋅100

B: 48.39%
B: 48 point 3 9 percent

A: |8.40−8.96|8.40⋅100
A: |8.40−8.96|8.40⋅100

B: 6.67%
B: 6 point 6 7 percent

A: 8.40|8.4+8.96|⋅100

Answer 1

To find the percent error, we use the formula:

\[
\text{Percent Error} = \left| \frac{\text{Measured Value} - \text{True Value}}{\text{True Value}} \right| \times 100
\]

Part A: The correct expression to calculate the percent error for the measured density of the copper sample is:

**A: |8.40−8.96|/8.96⋅100**

Part B: Now we need to calculate the percent error using this formula:

1. Calculate the absolute error:
\[
|8.40 - 8.96| = | -0.56 | = 0.56
\]

2. Divide by the true value (which is 8.96):
\[
\frac{0.56}{8.96} \approx 0.0625
\]

3. Convert to percentage:
\[
0.0625 \times 100 = 6.25\%
\]

Thus, the correct answer for Part B is:

**B: 6.25%**

So the selected responses would be:
- Part A: **A: |8.40−8.96|/8.96⋅100**
- Part B: **B: 6.25%**