$$\text{Formal charge} = \text{valence electrons} - \frac{1}{2} \times \text{bonding electrons} - \text{unpaired electrons}$$

Question 1

Which of the following statements best describes the role of neutrons in the atomic nucleus?

Accepted Answer

Neutrons contribute to the atomic mass but do not affect the charge.

Question 2

Given the electron configuration $$1s^2$$ $$2s^2$$ $$2p^3$$, which element does this represent and how many valence electrons does it have?

Accepted Answer

Nitrogen; 5 valence electrons

Question 3

Which principle states that electrons fill the lowest energy orbitals first?

Accepted Answer

Aufbau Principle

Question 4

What is the maximum number of electrons that can occupy a single p orbital?

Accepted Answer

2

Question 5

Which of the following best explains why atoms form chemical bonds?

Accepted Answer

To attain a filled outer shell of electrons

Question 6

Consider the Lewis structure for $$CH_3OCH_3 ($$dimethyl ether). How many lone pairs are present on the oxygen atom?

Accepted Answer

2

Question 7

Which of the following elements is most likely to form three covalent bonds in organic molecules?

Accepted Answer

Nitrogen

Question 8

What is the formal charge on the central carbon atom in the Lewis structure of $$CH_3CH_2CH=O ($$propanal)?

Accepted Answer

0

Question 9

Which rule states that no two electrons in an atom can have the same set of quantum numbers?

Accepted Answer

Pauli Exclusion Principle

Question 10

If an atom has 6 protons, 6 neutrons, and 6 electrons, what is its atomic number and mass number?

Accepted Answer

Atomic number: 6, Mass number: 12

Question 11

Which of the following best describes a node in an atomic orbital?

Accepted Answer

A region where the probability of finding an electron is zero

Question 12

How many electrons are present in the 2p orbitals of a carbon atom in its ground state?

Accepted Answer

2

Question 13

Which of the following is the correct electron configuration for oxygen?

Accepted Answer

$$1s^2$$ $$2s^2$$ $$2p^4$$

Question 14

Which of the following molecules contains a double bond?

Accepted Answer

$$C_2H_4$$

Question 15

What is the formal charge on the oxygen atom in the Lewis structure of formic acid ($$HCOOH$$)?

Accepted Answer

0

Question 16

Which of the following best describes the difference between ionic and covalent bonding?

Accepted Answer

Ionic bonding involves transferring electrons; covalent bonding involves sharing electrons.

Question 17

How many valence electrons does fluorine have, and what is its typical bonding pattern in organic molecules?

Accepted Answer

7 valence electrons; forms one single bond

Question 18

Which of the following is the correct formula for calculating the formal charge on an atom?

Accepted Answer

$$	ext{Formal charge} = 	ext{valence electrons} - \frac{1}{2} 	imes 	ext{bonding electrons} - 	ext{unpaired electrons}$$

Question 19

Which of the following elements is most likely to have a lone pair in its Lewis structure when bonded in organic molecules?

Accepted Answer

Nitrogen

Question 20

A molecule has the following Lewis structure: $$H_2C=CH_2$. What type of bond is present between the two carbon atoms?

Accepted Answer

Double bond

Lecture 2 part 1 Properties of Atoms & Bonds – CHEM 2311 Organic Chemistry I Study Notes

Study Guide - Practice Questions