Chemistry class 9 - 1st

The smallest particle of an element is called .................... .

• Atom
• Molecule
• Radical
• Crystal

Which of the given matter is not an element?

• Hydrogen
• Water
• Calcium
• Sodium

The smallest particle of a compound is called .................... .

• Molecule
• Atom
• Radical
• Crystal

Which of the given matter is not a compound?

• Water
• Ammonia
• Sulphur
• Lime stone

Which of the given is not a shell?

• K
• M
• L
• J

How many electrons will found in L-shell?

• 8
• 2
• 18
• 32

How many electrons in a shell can have d-subshell?

• 2
• 6
• 10
• 14

What do you mean by valance electron?

• The capacity of an element to take part in chemical reaction.
• Number of charge of a radical.
• Number of electon found in the outermost shell of an element.
• A type of electron.

What is the valancy of sodium?

• 4
• 3
• 2
• 1

What do you mean by inert gas?

• Highly reactive elements
• Chemically inactive elements
• Less reactive metals
• Elemets having more than one valancy