Question 1

Which of the following correctly describes the order of orbital filling according to the Aufbau principle?

Accepted Answer

$$1s \rightarrow 2s \rightarrow 2p \rightarrow 3s \rightarrow 3p \rightarrow 4s \rightarrow 3d \rightarrow 4p$$

Question 2

Which quantum number determines the shape of an atomic orbital?

Accepted Answer

The azimuthal (angular momentum) quantum number $$l$$

Question 3

How many possible orientations (values of $$m_l) $$are there for a $$d$$ orbital?

Accepted Answer

5

Question 4

Which of the following electron configurations represents a paramagnetic atom?

Accepted Answer

$$1s^2$$\ $$2s^2$$\ $$2p^3$$

Question 5

Which statement best explains why $$O_2 is $$paramagnetic, while $$N_2 is $$diamagnetic?

Accepted Answer

$$O_2$$ has unpaired electrons in its molecular orbitals, while $$N_2$$ does not.

Question 6

Which of the following molecules has a linear geometry according to VSEPR theory?

Accepted Answer

$$CO_2$$

Question 7

What is the hybridization of the central atom in $$BF_3$$?

Accepted Answer

$$sp^2$$

Question 8

Which of the following best describes the difference between a sigma ($$\sigma) $$and a pi ($$\pi) $$bond?

Accepted Answer

A $$\sigma$$ bond results from end-to-end overlap, while a $$\pi$$ bond results from side-to-side overlap.

Question 9

How many sigma ($$\sigma) $$and pi ($$\pi) $$bonds are present in the molecule $$C_2H_4 ($$ethylene)?

Accepted Answer

5 $$\sigma$$, 1 $$\pi$$

Question 10

Which of the following statements about electronegativity and bond type is correct?

Accepted Answer

A large difference in electronegativity between two atoms leads to an ionic bond.

Question 11

What is the molecular geometry of $$SF_6$$ according to VSEPR theory?

Accepted Answer

Octahedral

Question 12

Which of the following best describes the process of hybridization in the $$CH_4$$ molecule?

Accepted Answer

The carbon atom forms four equivalent $$sp^3$$ hybrid orbitals.

Question 13

Which of the following is a correct set of quantum numbers for an electron in a $$3d$$ orbital?

Accepted Answer

$$n=3,\ l=2,\ m_l=0$$

Question 14

Which molecule has a bond angle closest to $$120^\circ$$?

Accepted Answer

$$BF_3$$

Question 15

Which of the following best explains why the bond length in $$H_2 is $$shorter than in $$HI$$?

Accepted Answer

Hydrogen atoms are smaller than iodine atoms, resulting in a shorter bond.

Question 16

Which of the following is the correct Lewis structure for the carbonate ion $$CO_3$$^{2-}$$?

Accepted Answer

A structure with three resonance forms, each with a double bond to one oxygen and single bonds to the other two, with formal charges minimized.

Question 17

What is the bond order of $$O_2$$ according to molecular orbital theory?

Accepted Answer

$$2$$

Question 18

Which of the following best describes a diamagnetic substance?

Accepted Answer

A substance with all electrons paired

Question 19

Which hybridization is associated with a trigonal bipyramidal geometry?

Accepted Answer

$$sp^3d$

Atomic Structure, Chemical Bonding, and Molecular Geometry: Foundations for Organic Chemistry

Guida di studio - Domande di pratica