Question 1

Which of the following statements best describes an element?

Accepted Answer

An element is a pure substance from which all other things are built and cannot be broken down into simpler substances.

Question 2

Which of the following elements is correctly matched with its chemical symbol?

Accepted Answer

Magnesium – Mg

Question 3

Which group on the periodic table contains the alkali metals?

Accepted Answer

Group 1A (1)

Question 4

Which of the following best describes the location and charge of a proton in an atom?

Accepted Answer

Located in the nucleus with a positive charge

Question 5

A neutral atom of calcium has an atomic number of 20 and a mass number of 40. How many protons, neutrons, and electrons does it have?

Accepted Answer

$$20$$ protons, $$20$$ neutrons, $$20$$ electrons

Question 6

Which of the following statements about isotopes is correct?

Accepted Answer

Isotopes of an element have the same number of protons but different numbers of neutrons.

Question 7

A sample of gallium contains $$60.10\% of$$ $$^{69}\mathrm{Ga} ($$atomic mass $$68.926) $$and $$39.90\% of$$ $$^{71}\mathrm{Ga} ($$atomic mass $$70.925). $$What is the atomic mass of gallium?

Accepted Answer

$$69.72$$

Question 8

Which of the following best describes the trend in atomic size across a period from left to right?

Accepted Answer

Atomic size decreases due to increased nuclear charge.

Question 9

Which element is a metalloid and is commonly used in semiconductors?

Accepted Answer

Silicon

Question 10

Which of the following electron configurations represents a noble gas?

Accepted Answer

$$1s^2$$\ $$2s^2$$\ $$2p^6$$

Question 11

Which of the following statements about ionization energy is correct?

Accepted Answer

Ionization energy increases across a period from left to right.

Question 12

Which of the following elements has the highest metallic character?

Accepted Answer

Sodium

Question 13

Which of the following is the correct Lewis symbol for nitrogen?

Accepted Answer

N with five dots around it

Question 14

Which of the following best explains why the atomic mass of chlorine is not a whole number?

Accepted Answer

It is the weighted average of the masses of its naturally occurring isotopes.

Question 15

Which of the following statements about the Pauli exclusion principle is correct?

Accepted Answer

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

Question 16

Which of the following elements is essential for the formation of bones and teeth in the human body?

Accepted Answer

Calcium

Question 17

Which of the following best describes the difference between the s and p orbitals?

Accepted Answer

s orbitals are spherical, while p orbitals have a dumbbell shape.

Question 18

Which of the following is the correct order of filling for electron sublevels as atomic number increases?

Accepted Answer

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

Question 19

Which of the following elements has the greatest number of valence electrons?

Accepted Answer

Neon

Question 20

Which of the following best describes the trend in metallic character as you move down a group in the periodic table?

Accepted Answer

Metallic character increases.

Atoms and Elements: Structured Study Notes for GOB Chemistry

Study Guide - Practice Questions

Study Guide - Flashcards