You can find the density of water in a cylinder by measuring the mass of a known volume of water and then applying the density formula. Here's a step-by-step guide based on the reference:
Steps to Calculate Water Density
- Measure the Mass of an Empty Cylinder:
- Begin by placing an empty graduated cylinder on a scale.
- Record this mass carefully. This is the mass of the cylinder itself.
- Fill the Cylinder with Water:
- Pour a specific volume of water, such as 100 ml, into the graduated cylinder.
- Make sure to read the water level accurately at the meniscus (the curve of the water)
- Measure the Combined Mass:
- Place the graduated cylinder containing the water back onto the scale.
- Record the combined mass of the cylinder and the water.
- Calculate the Mass of Water:
- Subtract the mass of the empty cylinder (measured in step 1) from the combined mass of the cylinder and water (measured in step 3).
- This result is the mass of the water.
- Calculate Density:
- Density (ρ) is calculated using the formula: ρ = m/v, where 'm' is the mass of water, and 'v' is the volume of water.
- You already know the mass of water from the previous step, and the volume of water you added is already known (e.g. 100 mL).
- Divide the mass of the water by the volume of the water to determine the density.
Formula
- Density (ρ) = mass (m) / volume (v)
Example
Let's say:
- Mass of empty cylinder = 50 grams
- Mass of cylinder + 100 ml water = 150 grams
- Volume of water = 100 ml
- Mass of water = 150 grams - 50 grams = 100 grams
- Density of water = 100 grams / 100 ml = 1 gram/ml
Summary
| Step | Action | Measurement Needed |
|---|---|---|
| 1 | Measure mass of empty cylinder | Mass of empty cylinder |
| 2 | Fill cylinder with a known volume of water | Volume of water |
| 3 | Measure mass of cylinder with water | Mass of cylinder + water |
| 4 | Calculate the mass of the water | Mass of water |
| 5 | Calculate the density of the water using ρ = m/v | Density of water |
This method allows you to accurately find the density of water using basic lab tools and measurements.
