Chapter Name: Separation of Substances
Activity Name: A chalk with different colours in Separation of Substances
In this experiment, we will observe how water interacts with a chalk stick and the ink mark on its surface. By placing the chalk stick in water, we will observe the color patterns that form on the chalk over time.
We will also determine if the chalk absorbs water and if there are any changes in the ink mark.
- White chalk stick
- Blue or black ink
- Notebook for drawing and recording observations
Step by Step Procedure:
- Take a whole stick of white chalk.
- Using blue or black ink, make an ink mark around the curved surface of the chalk.
- Pour a small amount of water into a plate, ensuring that the water level is low and does not touch the ink mark.
- Gently place the chalk stick in the water, with the ink mark facing upwards. Make sure the water does not reach the top of the chalk.
- Observe the chalk over time and note the color patterns that form on the chalk’s surface.
- Check if the chalk absorbs water and if there are any changes in the ink mark.
- Remove the chalk from the water before the water reaches the top of the chalk stick.
- Observe the colors on the chalk from the bottom to the top and draw a picture of the chalk in your notebook.
- Make a note of the colors you have seen on the chalk.
- Reflect on where these colors might have come from.
- Color patterns form on the chalk’s surface over time.
- The chalk may or may not absorb water depending on the specific brand or composition.
- The ink mark may undergo changes due to interaction with water.
- Colors may be observed on the chalk from the bottom to the top.
- Handle the chalk stick and ink carefully to avoid spills or stains.
- Use a small amount of water to ensure the ink mark is not submerged.
- Remove the chalk from the water before the water reaches the top to prevent excessive soaking.
Lesson Learnt from Experiment:
This experiment demonstrates that water can interact with the surface of a chalk stick, causing color patterns to form. The chalk may or may not absorb water, depending on its composition.
The ink mark on the chalk can also undergo changes when exposed to water. The colors observed on the chalk may come from the ink dissolving or spreading on the chalk’s surface due to water interaction.