Question

answer the following questions (you must show your work to receive full credit)

1. why do you think the density calculated in the above table is only an approximate value?
2. calculate the density of a 150g solid that displaces 7.8ml of water.
3. calculate the volume of a piece of glass that weighs 35.8g and has a density of 2.5g/cm³.

Explanation:

Step1: Recall density formula

Density $
ho=\frac{m}{V}$, where $m$ is mass and $V$ is volume. Measurement errors affect density.

Step2: Answer question 1

In real - world measurements, there are errors in measuring mass and volume. Measuring instruments have limited precision. Also, the object's shape might not be regular, leading to inaccuracies in volume measurement. So, density is approximate.

Step3: Answer question 2

Given $m = 150g$ and $V=7.8ml = 7.8cm^{3}$ (since $1ml = 1cm^{3}$). Using the density formula $
ho=\frac{m}{V}$, we have $
ho=\frac{150g}{7.8cm^{3}}\approx19.23g/cm^{3}$.

Step4: Answer question 3

Given $m = 35.8g$ and $
ho = 2.5g/cm^{3}$. Rearranging the density formula $V=\frac{m}{
ho}$, we get $V=\frac{35.8g}{2.5g/cm^{3}} = 14.32cm^{3}$.

Answer:

1. There are measurement errors in mass and volume due to limited - precision instruments and irregular object shapes.
2. Approximately $19.23g/cm^{3}$
3. $14.32cm^{3}$