Balancing Nuclear Equations Quiz: Master Nuclear Reactions

1. In nuclear equations, which must be conserved?

Temperature

Colour

Mass number a and atomic number z

Volume

Concept: conservation in nuclear equations. Nuclear reactions conserve nucleon number and charge. That means the totals of a (nucleons) and z (protons/charge) must match on both sides.

Explanation

Concept: conservation in nuclear equations. Nuclear reactions conserve nucleon number and charge. That means the totals of a (nucleons) and z (protons/charge) must match on both sides.

2. The atomic number z equals the number of protons.

True

False

Concept: meaning of z. z defines the element. Changing z changes the element, which is why beta decay changes one element into another.

Explanation

Concept: meaning of z. z defines the element. Changing z changes the element, which is why beta decay changes one element into another.

3. A neutron has:

A=0, z=1

A=1, z=0

A=0, z=0

A=2, z=1

Concept: a and z of a neutron. Neutron is one nucleon, no charge. So it contributes 1 to mass number a but 0 to atomic number z.

Explanation

Concept: a and z of a neutron. Neutron is one nucleon, no charge. So it contributes 1 to mass number a but 0 to atomic number z.

4. An alpha particle has a= and z=.

Concept: alpha particle identity. Alpha = helium nucleus (2p + 2n). It has 4 total nucleons (a=4) and 2 protons (z=2).

Explanation

Concept: alpha particle identity. Alpha = helium nucleus (2p + 2n). It has 4 total nucleons (a=4) and 2 protons (z=2).

Submit

5. In beta-minus (β-) decay, z changes by:

-2

-1

+1

0

Concept: beta-minus nuclear change. Neutron → proton + electron. The proton count increases by 1, so z increases by 1 while a stays the same.

Explanation

Concept: beta-minus nuclear change. Neutron → proton + electron. The proton count increases by 1, so z increases by 1 while a stays the same.

6. In β- decay, mass number a stays the same.

True

False

Concept: nucleon conservation in beta decay. Total nucleons unchanged. A neutron becomes a proton, so the total number of nucleons in the nucleus does not change.

Explanation

Concept: nucleon conservation in beta decay. Total nucleons unchanged. A neutron becomes a proton, so the total number of nucleons in the nucleus does not change.

7. Complete the reaction: (_7^14)n + (_0^1)n → (_6^14)c + x. What is x?

(_0^1)n

(_1^1)p

(2^4)he

(-1^0)e

Concept: balancing a and z. Balance a: 14+1=15 → 14 + a(x) so a(x)=1. Left z=7, right has 6 + z(x) → z(x)=1, so x is a proton (_1^1)p.

Explanation

Concept: balancing a and z. Balance a: 14+1=15 → 14 + a(x) so a(x)=1. Left z=7, right has 6 + z(x) → z(x)=1, so x is a proton (_1^1)p.

8. If (_92^235)u absorbs a neutron, the compound nucleus first formed is:

(_92^235)u

(_92^236)u

(_92^234)u

(_93^236)np

Concept: neutron capture effect on a and z. Adding a neutron increases a by 1, z unchanged. So uranium stays uranium (z=92) but mass number becomes 236.

Explanation

Concept: neutron capture effect on a and z. Adding a neutron increases a by 1, z unchanged. So uranium stays uranium (z=92) but mass number becomes 236.

9. In fission, total a and total z must balance when you include emitted neutrons.

True

False

Concept: conservation in fission. Conservation laws apply. If neutrons are emitted, they must be counted in a (and z=0) when checking balance.

Explanation

Concept: conservation in fission. Conservation laws apply. If neutrons are emitted, they must be counted in a (and z=0) when checking balance.

10. A common fission channel is: (_^235)u + n → ^141 'ba' + ^92 'kr' + 3n. This shows:

Mass number is not conserved

Mass number is conserved

Charge is not conserved

Temperature is conserved

Concept: checking mass number balance. a balances properly. The sum of mass numbers on the right equals the left when neutrons are included.

Explanation

Concept: checking mass number balance. a balances properly. The sum of mass numbers on the right equals the left when neutrons are included.

11. In nuclear equations, we balance the totals of a and z on both ______.

Concept: balancing rule. Like balancing chemical equations, but with a and z. You make sure total nucleons and total charge match on left and right.

Explanation

Concept: balancing rule. Like balancing chemical equations, but with a and z. You make sure total nucleons and total charge match on left and right.

Submit

12. Complete: (_2^4)he + (_4^9)be → (_6^12)c + x. What is x?

(_0^1)n

(_1^1)p

(-1^0)e

Concept: balancing a and z to identify x. a: 4+9=13; carbon-12 leaves 1 → neutron. z: 2+4=6; carbon has 6, so x has z=0.

Explanation

Concept: balancing a and z to identify x. a: 4+9=13; carbon-12 leaves 1 → neutron. z: 2+4=6; carbon has 6, so x has z=0.

13. A gamma ray can appear in an equation as (_0^0)γ.

True

False

Concept: gamma in nuclear equations. Gamma has a=0, z=0. It represents energy emitted from the nucleus without changing nucleon number or charge.

Explanation

Concept: gamma in nuclear equations. Gamma has a=0, z=0. It represents energy emitted from the nucleus without changing nucleon number or charge.

14. In neutron capture followed by gamma emission: (_z^a)x + n → _z^(a+1)x + γ. Which changes?

Z changes

A increases by 1, z stays the same

A decreases by 1

Both a and z decrease

Concept: neutron capture changes. Neutron adds mass number only. Gamma emission releases energy, but does not change a or z.

Explanation

Concept: neutron capture changes. Neutron adds mass number only. Gamma emission releases energy, but does not change a or z.

15. Which particles have a=0? (Select multiple answers)

Gamma ray

Electron (β-)

Alpha particle

Neutron

Concept: a values for common particles. Gamma and electron have a=0; alpha has a=4; neutron has a=1. a counts nucleons, and electrons/photons are not nucleons.

Explanation

Concept: a values for common particles. Gamma and electron have a=0; alpha has a=4; neutron has a=1. a counts nucleons, and electrons/photons are not nucleons.

Submit

16. A proton can be written as (_1^1)p in nuclear equations.

True

False

Concept: proton notation. a=1, z=1. It contributes one nucleon and one unit of positive charge.

Explanation

Concept: proton notation. a=1, z=1. It contributes one nucleon and one unit of positive charge.

17. If a nucleus emits an alpha particle, its z decreases by 2, and a decreases by:

2

4

1

0

Concept: alpha emission effect. Alpha removes 2 protons + 2 neutrons. That reduces mass number by 4 and atomic number by 2.

Explanation

Concept: alpha emission effect. Alpha removes 2 protons + 2 neutrons. That reduces mass number by 4 and atomic number by 2.

18. The reaction (_2^1)h + ^3h → ^4he + n is:

Fission

Fusion

Beta decay

Chemical reaction

Concept: identifying fusion. Two light nuclei combine. Deuterium and tritium join to form helium-4 and a neutron, releasing energy.

Explanation

Concept: identifying fusion. Two light nuclei combine. Deuterium and tritium join to form helium-4 and a neutron, releasing energy.

19. In the d-t fusion reaction, total a is 2+3=5 and total z is 1+1=2; products have a 4+1=5 and z 2+0=2.

True

False

Concept: conservation check. Both conserve. The totals of a and z match on both sides when you include the emitted neutron.

Explanation

Concept: conservation check. Both conserve. The totals of a and z match on both sides when you include the emitted neutron.

20. Best grade 11 summary: balancing nuclear reactions is done by conserving:

Speed and pressure

Mass number a and atomic number z

Colour and brightness

Temperature and volume

Concept: core balancing rule. a and z conservation is the core rule. If both totals match, the nuclear equation is properly balanced.

Explanation

Concept: core balancing rule. a and z conservation is the core rule. If both totals match, the nuclear equation is properly balanced.

Balancing Nuclear Equations Quiz: Practice Reaction Balancing

1. In nuclear equations, which must be conserved?

2.

What first name or nickname would you like us to use?

2. The atomic number z equals the number of protons.

3. A neutron has:

4. An alpha particle has a= and z=.

5. In beta-minus (β-) decay, z changes by:

6. In β- decay, mass number a stays the same.

7. Complete the reaction: (_7^14)n + (_0^1)n → (_6^14)c + x. What is x?

8. If (_92^235)u absorbs a neutron, the compound nucleus first formed is:

9. In fission, total a and total z must balance when you include emitted neutrons.

10. A common fission channel is: (_^235)u + n → ^141 'ba' + ^92 'kr' + 3n. This shows:

11. In nuclear equations, we balance the totals of a and z on both ______.

12. Complete: (_2^4)he + (_4^9)be → (_6^12)c + x. What is x?

13. A gamma ray can appear in an equation as (_0^0)γ.

14. In neutron capture followed by gamma emission: (_z^a)x + n → _z^(a+1)x + γ. Which changes?

15. Which particles have a=0? (Select multiple answers)

16. A proton can be written as (_1^1)p in nuclear equations.

17. If a nucleus emits an alpha particle, its z decreases by 2, and a decreases by:

18. The reaction (_2^1)h + ^3h → ^4he + n is:

19. In the d-t fusion reaction, total a is 2+3=5 and total z is 1+1=2; products have a 4+1=5 and z 2+0=2.

20. Best grade 11 summary: balancing nuclear reactions is done by conserving:

Balancing Nuclear Equations Quiz: Practice Reaction Balancing

1. In nuclear equations, which must be conserved?

2.

What first name or nickname would you like us to use?

2. The atomic number z equals the number of protons.

3. A neutron has:

4. An alpha particle has a=____ and z=____.

5. In beta-minus (β-) decay, z changes by:

6. In β- decay, mass number a stays the same.

7. Complete the reaction: (_7^14)n + (_0^1)n → (_6^14)c + x. What is x?

8. If (_92^235)u absorbs a neutron, the compound nucleus first formed is:

9. In fission, total a and total z must balance when you include emitted neutrons.

10. A common fission channel is: (_^235)u + n → ^141 'ba' + ^92 'kr' + 3n. This shows:

11. In nuclear equations, we balance the totals of a and z on both ______.

12. Complete: (_2^4)he + (_4^9)be → (_6^12)c + x. What is x?

13. A gamma ray can appear in an equation as (_0^0)γ.

14. In neutron capture followed by gamma emission: (_z^a)x + n → _z^(a+1)x + γ. Which changes?

15. Which particles have a=0? (Select multiple answers)

16. A proton can be written as (_1^1)p in nuclear equations.

17. If a nucleus emits an alpha particle, its z decreases by 2, and a decreases by:

18. The reaction (_2^1)h + ^3h → ^4he + n is:

19. In the d-t fusion reaction, total a is 2+3=5 and total z is 1+1=2; products have a 4+1=5 and z 2+0=2.

20. Best grade 11 summary: balancing nuclear reactions is done by conserving:

4. An alpha particle has a= and z=.