Question 1

Which of the following statements correctly describes the difference between atomic number and mass number for an atom?

Accepted Answer

Atomic number is the number of protons, while mass number is the sum of protons and neutrons.

Question 2

A neutral atom of carbon-14 ($$^{14}_{6}C) $$has how many protons, neutrons, and electrons?

Accepted Answer

6 protons, 8 neutrons, 6 electrons

Question 3

Which type of radiation has the greatest penetrating power and is most likely to cause ionization deep within biological tissue?

Accepted Answer

Gamma ($$\gamma) $$radiation

Question 4

Which of the following best describes a radioisotope?

Accepted Answer

An isotope with an unstable nucleus that spontaneously emits radiation.

Question 5

Given the nuclear equation $$^{226}_{88}Ra \$$rightarrow ^{222}$$_{86}Rn $$+ ^{4}$$_{2}\alpha$$, how many protons and neutrons are in the daughter nuclide $$^{222}_{86}Rn$$?

Accepted Answer

86 protons, 136 neutrons

Question 6

Which element is classified as a metalloid and displays properties intermediate between metals and nonmetals?

Accepted Answer

Silicon (Si)

Question 7

If the half-life of cerium-141 is 32.5 days, how much of a 10.0-g sample remains after three half-lives?

Accepted Answer

1.25 g

Question 8

Which of the following is the correct electron configuration for a neutral atom of beryllium (atomic number 4)?

Accepted Answer

$$1s^2$$\ $$2s^2$$

Question 9

Which of the following best explains why alpha particles have low penetrating power compared to beta and gamma radiation?

Accepted Answer

Alpha particles are larger and have a +2 charge, causing them to interact strongly with matter and lose energy quickly.

Question 10

Which of the following nuclear equations represents beta ($$\beta) $$decay?

Accepted Answer

$$^{14}_{6}C \$$rightarrow ^{14}$$_{7}N $$+ ^{0}$$_{-1}\beta$$

Question 11

Which of the following is NOT a main group element?

Accepted Answer

Iron (Fe)

Question 12

What is the charge and location of a neutron in an atom?

Accepted Answer

Neutral (0), located in the nucleus

Question 13

Which of the following best describes valence electrons?

Accepted Answer

Electrons in the highest energy level of an atom that are involved in chemical bonding

Question 14

A radioactive isotope emits a beta particle. What happens to its atomic number and mass number?

Accepted Answer

Atomic number increases by 1, mass number remains unchanged

Question 15

Which of the following is a real-world application of a radioisotope in medicine?

Accepted Answer

Using technetium-99m ($$^{99m}_{43}Tc) $$for imaging organs in nuclear medicine scans

Question 16

Which equation correctly relates the energy of electromagnetic radiation to its frequency?

Accepted Answer

$$E = h 
u$$

Question 17

Which of the following statements about the periodic table is correct?

Accepted Answer

Elements in the same group have similar chemical properties due to similar valence electron configurations.

Question 18

Which type of radiation is most likely to cause mutations in DNA due to its ionizing power?

Accepted Answer

Gamma rays and high-energy ultraviolet radiation

Question 19

A sample of iodine-131 ($$^{131}_{53}I) $$undergoes beta decay. What is the daughter nuclide?

Accepted Answer

$$^{131}_{54}Xe$$

Question 20

Which of the following best explains why background radiation is always present in our environment?

Accepted Answer

It comes from natural sources such as cosmic rays, radioactive elements in the earth, and organic molecules.

Atomic Structure and Radioisotopes: Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard