A student calculates the density of iron as 6.6 g/cm3 using lab data for mass and volume. A handbook reveals that the correct value is 7.57 g/cm3. What is the percent error?

1 Answer
Sep 20, 2017

#% "error" = 12.8%#

Explanation:

Percent error is calculated using the following formula:

#Rightarrow % "error" = |frac("experimental value" - "theoretical value")("theoretical value")| cdot 100#

This formula can be refined as:

#Rightarrow % "error" = |frac("experimental value")("theoretical value") - frac("theoretical value")("theoretical value")| cdot 100#

#Rightarrow % "error" = |frac("experimental value")("theoretical value") - 1| cdot 100#

Now, let's substitute the relevant values into the formula:

#Rightarrow % "error" = |frac(6.6" g/cm"^(3))(7.57" g/cm"^(3)) - 1| cdot 100#

#Rightarrow % "error" = |0.8718626156 - 1| cdot 100#

#Rightarrow % "error" = |- 0.1281373844| cdot 100#

#Rightarrow % "error" = 0.1281373844 cdot 100#

#Rightarrow % "error" = 12.81373844%#

#therefore % "error" approx 12.8%#

Therefore, the percent error is around #12.8%#.