Structure of the atom revision

What is the correct configuration of potassium atom?

• 2, 8,10

• 2,8,9

• 2,8,8,1

• 2,8,8

Which of the following elements has the stable electronic configuration and is inert?

• Sodium

• Sulphur

• Phosphorus

• Argon

Can the number of protons and neutrons change in an atom?

• Yes, they can move like electrons do

• No, they don't participate in reactions

• No, the are in nucleus and only change in radioactive decay

• Yes, but only neutrons.

Check the correct configuration of sodium ion

• 2,8,8

• 2,8

• 2,8,1

• 2,7

Substance A and B combine in the ratio 5:3 to form a product C.

How much of B is used to form 80g of C?

• 50g

• 58g

• 38g

• 30g

If A and B completely react to form 48g of C when 20g of A was used, how much B will be used in the reaction?

• 38g

• 48g

• 28g

• 18g

Which of these elements has 4 electrons in its M shell?

• Carbon

• Silicon

• Oxygen

• Chlorine

What was Rutherford expecting to see in his experiment?

• All alpha rays would be deflected by the positive sphere

• All alpha rays would pass undeflected in the positive sphere

• Some rays would deflect

• All rays would deflect

Which law of chemical combination explains that the mass is not created during a chemical change?

• Law of definite proportions

• Law of Conservation of mass

• Both A&B

• None of the above

Check all the postulates of planetary model of the atom.

• Electrons can exist in different energy levels, but these energy levels are fixed.

• Electrons are embedded outside the nucleus

• Electrons revolve around the nucleus in circular energy levels

• Electrons can be filled in random orders in the levels