Q: Which of the following is a real-world application of radioisotopes in medicine?

Imaging and biological labeling using $$^{99m}\text{Tc}$$

Question 1

Which of the following statements best explains why life primarily uses elements such as hydrogen, carbon, nitrogen, and oxygen?

Accepted Answer

They are among the most abundant elements in the Earth's crust and possess suitable physical and chemical properties for biological processes.

Question 2

A sample contains two isotopes of chlorine: $$^{35}	ext{Cl} (75$$%) and $$^{37}	ext{Cl} (25$$%). What is the average atomic mass of chlorine in this sample?

Accepted Answer

$$35.5$$

Question 3

Which technique is most commonly used in modern biology to identify biomolecules in complex mixtures and to discover isotopes?

Accepted Answer

Mass spectrometry

Question 4

If you have exactly $$12$$ grams of carbon-12, how many atoms do you have?

Accepted Answer

$$6.022 	imes 10$$^{23}$$

Question 5

Which of the following best describes the Pauli Principle?

Accepted Answer

Each orbital can hold a maximum of two electrons with opposite spins.

Question 6

A radioactive isotope has a half-life ($$t_{1/2}) of$$ $$6$$ hours. If you start with $$100$$ grams, how much will remain after $$18$$ hours?

Accepted Answer

$$12.5$$ grams

Question 7

Which fundamental interaction is responsible for holding protons and neutrons together in the nucleus?

Accepted Answer

Strong interaction

Question 8

Which of the following statements about electronic configuration is correct?

Accepted Answer

Electrons fill orbitals in order of increasing energy, starting from the lowest energy orbital.

Question 9

Which orbital types are present in the third shell ($$n=3) of an $$atom?

Accepted Answer

One s, three p, and five d orbitals

Question 10

Which of the following best describes Hund’s Rule?

Accepted Answer

Electrons occupy different orbitals of equal energy with parallel spins before pairing up.

Question 11

Why are many Fe(III) compounds difficult for organisms to absorb?

Accepted Answer

They are insoluble in water, reducing their bioavailability.

Question 12

Which of the following is NOT a type of nuclear radiation released during radioactive decay?

Accepted Answer

Neutron emission

Question 13

What is the molar mass ($$M) of $$glucose ($$	ext{C}_6	ext{H}_{12}	ext{O}_6$$)?

Accepted Answer

$$180.16\ 	ext{g mol}^{-1}$$

Question 14

Which statement about isotopes is correct?

Accepted Answer

Isotopes have the same atomic number but different mass numbers.

Question 15

Which of the following best describes the quantum mechanical model of the atom?

Accepted Answer

Electrons are described by wavefunctions and occupy orbitals with uncertain positions and speeds.

Question 16

Which element would you expect to have the highest abundance in the Earth's crust based on the periodic table and abundance graph?

Accepted Answer

Oxygen

Question 17

Which electron in a neutral atom has the highest energy and is most likely to be removed during ionization?

Accepted Answer

A valence electron

Question 18

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

Accepted Answer

Imaging and biological labeling using $$^{99m}	ext{Tc}$$

Question 19

Which principle explains why electrons fill the lowest energy orbitals first?

Accepted Answer

Aufbau Principle

Question 20

Which of the following best explains the structure of the periodic table?

Accepted Answer

Electronic configurations determine the arrangement and group similarities of elements.

Atoms and Elements: Foundations of Biochemistry

Guida di studio - Domande di pratica

Study guide - Flashcard