Chapter: 01. Matter
CHECK YOUR PROGRESS
Which is the smallest possible unit of matter? Matter can have more mass, even if it occupies REASON CORNER
Why is it easier to break a piece of coal than a piece of iron?
It is easier to break a piece of coal than a piece of iron because the intermolecular forces of attraction between the molecules in coal are weaker compared to the very strong intermolecular forces of attraction in iron. CHECK YOUR PROGRESS
Which of the following cannot flow? Which of the following cannot be compressed very easily? Which of the following does not have a fixed shape but has fixed volume? PREPPING FOR PIGA
Assertion (A): In diffusion, molecules move in a random manner.
Reason ®: Diffusion can take place in all directions. b. Both A and R are true, but R is not the correct explanation of A. A few drops of ink are added to the beakers A and B containing equal amounts of water. The water in Beaker A has a temperature of 20° C and the water in Beaker B has a temperature of 40° C. In which beaker will diffusion take place faster and why? Diffusion will take place faster in Beaker B (40° C) because higher temperature increases the kinetic energy of molecules, causing them to move faster and spread out more quickly. EVALUATION
A. Choose the correct option.
Which of the following has the least intermolecular space? What do we call the force of attraction between molecules? c. Intermolecular force of attraction On dissolving 40 g of salt in 75 mL of water, it is observed that there is no increase in its volume. Which property of the molecules of a liquid (water) is not responsible for this observation? c. The molecules have high force of attraction between them. B. Fill in the blanks.
Atoms combine to form molecules. When we fill a closed container with gas it spreads out and occupies the entire available space. Unlike liquids, solids have strong intermolecular force of attraction. The three different forms of matter are known as the three states of matter. C. Write true (T) or false (F) against the following statements.
The greater the intermolecular space, the lesser will be the intermolecular force of attraction. All solids have fixed shape and volume. Oxygen and carbon dioxide are examples of liquids. The space between the molecules in a matter is known as particle space. False (F) (It is known as intermolecular space) D. Short answer type questions.
What is matter? What are its two essential properties? Matter is anything that has mass and occupies space. Its two essential properties are having mass and occupying space (volume). 
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