Question 1

Which of the following best describes the process of alpha decay?

Accepted Answer

A nucleus emits a helium-4 nucleus, reducing its atomic number by 2 and mass number by 4.

Question 2

Which equation correctly represents the beta decay of $$^{14}C$$?

Accepted Answer

$$^{14}C \$$rightarrow ^{14}$$N + e$$^{-}$$

Question 3

A radioactive isotope has a half-life of 10 years. If you start with 80 grams, how much will remain after 30 years?

Accepted Answer

20 grams

Question 4

Which of the following is a correct statement about nuclear fusion?

Accepted Answer

It combines light nuclei to form a heavier nucleus, releasing energy.

Question 5

Which formula is used to calculate the mass defect ($$\Delta m) of a $$nucleus?

Accepted Answer

$$\Delta m = Zm_p + Nm_n - m_{nucleus}$$

Question 6

Which of the following is NOT a use of radioactive isotopes in medicine?

Accepted Answer

Increasing the nutritional value of food

Question 7

What is the nuclear binding energy ($$E_b) of a $$nucleus with a mass defect of $$0.02 u$$? (Use $$1 u$$ $$= 931.5$$ MeV)

Accepted Answer

$$E_b = 18.63$$ MeV

Question 8

Which of the following is true about the stability of a nucleus?

Accepted Answer

Stability is determined by the ratio of protons to neutrons.

Question 9

Which type of radioactive decay is responsible for the emission of a positron?

Accepted Answer

Beta-plus decay

Question 10

A sample contains $$^{238}U$$ and $$^{206}Pb. $$Which dating method would be most appropriate to determine its age?

Accepted Answer

Uranium-lead dating

Question 11

Which equation describes the rate of radioactive decay?

Accepted Answer

$$N = N_0$ e$$^{-\lambda t}$$

Question 12

Which of the following statements about radiocarbon dating is correct?

Accepted Answer

It measures the ratio of $$^{14}C to$$ $$^{12}C in $$organic material.

Question 13

Which of the following is a product of positron emission?

Accepted Answer

A proton is converted into a neutron.

Question 14

If a radioactive sample decays to 25% of its original amount in 6 hours, what is its half-life?

Accepted Answer

3 hours

Question 15

Which of the following is a common misconception about nuclear fission?

Accepted Answer

It is the process that powers the sun.

Question 16

Which of the following is the correct nuclear equation for the alpha decay of $$^{226}Ra$$?

Accepted Answer

$$^{226}Ra \$$rightarrow ^{222}$$Rn $$+ ^{4}$$He$$

Question 17

Which of the following best explains why gamma emission does not change the atomic number or mass number of a nucleus?

Accepted Answer

Gamma emission releases energy without changing the number of protons or neutrons.

Question 18

Which of the following is the correct formula for calculating the energy released in a nuclear reaction using Einstein's equation?

Accepted Answer

$$E = mc^2$

Question 19

Which of the following is a real-world application of nuclear chemistry in power generation?

Accepted Answer

Using nuclear fission in reactors to produce steam for turbines

Question 20

A patient is injected with a radioactive tracer for a PET scan. Which type of decay is most relevant to this procedure?

Accepted Answer

Positron emission (beta-plus decay)

Introduction to Radioactivity and Nuclear Chemistry

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