Advertisements
Advertisements
Question
Describe a method to separate a mixture of common salt and sand.
Advertisements
Solution
Separation of common salt and sand from a mixture involves the processes of filtration, followed by evaporation.
Sand can be separated from a mixture of sand and salt solution (salt dissolved in water) by filtration. After filtration, sand remains on the filter paper as a residue. Common salt can now be obtained from the filtrate by boiling it. Boiling causes all the water to evaporate and salt is left behind. This process is called evaporation.
APPEARS IN
RELATED QUESTIONS
Match the following
| Column A | Column B | ||
| (a) | Molecules | (i) | Water boils |
| (b) | 100° C | (ii) | Evaporation |
| (c) | 0° C | (iii) | Changes from solid to gas |
| (d) | At all temperatures | (iv) | Matter |
| (e) | Camphor | (v) | Water freezes |
Give one difference between atoms and molecules.
Define matter. Give four examples of matter.
When a crystal of potassium permanganate is placed at the bottom of water in a beaker, the water in the whole beaker turns purple on its own, even without stirring. This is an example of :
The best evidence for the existence and movement of particles in liquids was provided by :
When extremely small particles X derived from the anther of a flower were suspended in a liquid Y and observed through a microscope, it was found that the particles X were moving throughout the liquid Y in a very zig-zag way. It was also observed that warmer the liquid Y, faster the particles X moved on its surface.
- What could particles X be ?
- What do you think liquid Y is ?
- What is the zig-zag movement of X known as ?
- What is causing the zig-zag movement of particles X ?
- Name the scientist who discovered this phenomenon.
- What does this experiment tell us about the nature of liquid Y?
Name the property which enables metals to be drawn into wires.
What is meant by saying that non-metals are brittle ?
Name one element, one compound and one mixture.
Classify the following into elements and compounds :
- H2O
- He
- Cl2
- CO
- Co
Name a metal which can be easily cut with a knife.
What is the name of the clear liquid formed when a solid dissolves in a liquid ?
If 25 mL of acetone is present in 150 mL of its aqueous solution, calculate the concentration of solution.
Which of the following represents the solubility of sugar in water at 20°C ?
Which method is better for recovering sugar from sugar solution : evaporation or crystallisation ? Give reason
for your answer.
The particles in the matter are extremely small and can be seen even with a powerful microscope.
What type of matter glass is?
The physical state of water at 373 K is ______.
______ is used for industrial refrigeration and transporting frozen food.
Write a scientific reason.
Lemon sherbat has a sweet, sour and salty taste and it can be poured in a glass.
