A form two student in physics laboratory was provided with density bottle, sand, digital balance and water. He is required to determine the density of sand using the instruments provided above, show how he will determine the density of sand?

- Mass of density bottle; M1 = 200g
- Mass of density bottle and sand M2 = 550g
- Mass of density bottle and water, M4=300g
What is the density of sand

1 answer

To determine the density of sand using the provided instruments, the student can follow these steps:

Step 1: Measure the mass of the sand

The mass of the sand can be calculated using the mass of the density bottle with sand and the mass of the empty density bottle: \[ \text{Mass of sand} (M_s) = M_2 - M_1 \] Where:

  • \(M_2 = 550 , \text{g}\) (mass of density bottle and sand)
  • \(M_1 = 200 , \text{g}\) (mass of density bottle)

Calculating: \[ M_s = 550 , \text{g} - 200 , \text{g} = 350 , \text{g} \]

Step 2: Determine the volume of the sand

Next, we find the volume of water displaced by the sand when it is placed in the density bottle. The mass of the density bottle with water is given as:

  • \(M_4 = 300 , \text{g}\) (mass of density bottle and water)

The volume of water (which will be the same volume as the sand, since they occupy the same space when the sand is added) can be calculated using the mass of the density bottle with water and the mass of the empty density bottle: \[ \text{Mass of water} (M_w) = M_4 - M_1 \] Calculating: \[ M_w = 300 , \text{g} - 200 , \text{g} = 100 , \text{g} \]

Now, convert the mass of water to volume. The density of water is approximately \(1 , \text{g/cm}^3\), thus: \[ \text{Volume of water} (V_w) = \text{Mass of water} = 100 , \text{cm}^3 \]

Step 3: Calculate the density of sand

The density of the sand can now be calculated using the formula for density: \[ \text{Density} (\rho) = \frac{\text{Mass}}{\text{Volume}} \] Substituting the values we have: \[ \rho_s = \frac{M_s}{V_w} = \frac{350 , \text{g}}{100 , \text{cm}^3} \]

Calculating: \[ \rho_s = 3.5 , \text{g/cm}^3 \]

Conclusion

The density of the sand is 3.5 g/cm³.