Q: Which of the following is the correct formula to calculate formal charge?

$$\text{Formal charge} = \text{Number of valence electrons} - (\text{Number of non-bonding electrons} + \frac{1}{2} \times \text{Number of bonding electrons})$$

Question 1

Which of the following molecules has the greatest dipole moment?

Accepted Answer

Ammonia ($$\mathrm{NH_3$})$$

Question 2

Which statement best explains why water ($$\mathrm{H_2O}) $$has a bent molecular geometry?

Accepted Answer

Because the lone pairs on oxygen repel the bonding pairs, resulting in a bent shape.

Question 3

Given the following Lewis structure for nitrate ion ($$\mathrm{NO_3$^-}$$), what is the formal charge on the central nitrogen atom?

Accepted Answer

$$+1$$

Question 4

Which of the following best describes the hybridization of the carbon atom in ethene ($$\mathrm{C_2H_4}$$)?

Accepted Answer

$$sp^2$$

Question 5

Which of the following molecules is expected to have a linear geometry?

Accepted Answer

Carbon dioxide ($$\mathrm{CO_2$})$$

Question 6

How many sigma ($$\sigma) $$and pi ($$\pi) $$bonds are present in the molecule acetylene ($$\mathrm{C_2H_2}$$)?

Accepted Answer

3 sigma, 2 pi

Question 7

Which of the following factors increases the strength of an acid?

Accepted Answer

Increasing resonance stabilization of the conjugate base

Question 8

Which representation best shows the three-dimensional arrangement of atoms in a molecule?

Accepted Answer

Ball-and-stick model

Question 9

What is the bond angle in a molecule with $$sp^3$$ hybridization and no lone pairs on the central atom?

Accepted Answer

$$109.5^\circ$$

Question 10

Which of the following acids is the strongest, based on $$pK_a$$ values?

Accepted Answer

Hydrochloric acid ($$pK_a = -6)$$

Question 11

Which of the following statements about covalent bonding is correct?

Accepted Answer

Covalent bonds involve the sharing of electron pairs between atoms.

Question 12

Which of the following molecules has a nonzero dipole moment?

Accepted Answer

Ammonia ($$\mathrm{NH_3$})$$

Question 13

Which of the following is the correct formula to calculate formal charge?

Accepted Answer

$$	ext{Formal charge} = 	ext{Number of valence electrons} - (	ext{Number of non-bonding electrons} + \frac{1}{2} 	imes 	ext{Number of bonding electrons})$$

Question 14

Which of the following best explains why $$\mathrm{HF} is a $$stronger acid than $$\mathrm{H_2O}$$?

Accepted Answer

The $$\mathrm{F^-}$$ ion is more stable due to its high electronegativity.

Question 15

Which of the following molecules contains both $$\sigma$$ and $$\pi$$ bonds?

Accepted Answer

Ethene ($$\mathrm{C_2H_4})$$

Question 16

Which of the following factors does NOT affect acid strength?

Accepted Answer

Atomic mass

Question 17

Which of the following is the correct order of increasing electronegativity?

Accepted Answer

Na \u003c C \u003c N \u003c F

Question 18

Which of the following is the best description of a conjugate base?

Accepted Answer

A species formed when an acid loses a proton.

Question 19

Which of the following molecules has a trigonal planar geometry?

Accepted Answer

Boron trifluoride ($$\mathrm{BF_3$})$$

Question 20

Which of the following statements about $$pK_a is $$correct?

Accepted Answer

A lower $$pK_a$$ value indicates a stronger acid.

General Chemistry Study Notes: Atomic Structure, Bonding, and Acid-Base Concepts

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