Question 1

Which of the following best describes an element according to the study materials?

Accepted Answer

A substance that cannot be broken down into another substance.

Question 2

What distinguishes one element from another?

Accepted Answer

The atomic number, which is the number of protons.

Question 3

Why do elements form compounds or molecules?

Accepted Answer

To achieve a stable electron configuration by sharing or transferring valence electrons.

Question 4

Which of the following is a correct example of a compound as described in the notes?

Accepted Answer

$$ \mathrm{Na} + \mathrm{Cl} \rightarrow \mathrm{NaCl} $$

Question 5

What is the electron configuration for the first shell of an atom?

Accepted Answer

1s orbital

Question 6

Which statement about compounds is supported by the study materials?

Accepted Answer

Compounds consist of two or more elements in a fixed ratio.

Question 7

How are atoms held together in a compound?

Accepted Answer

By sharing or transferring electrons to achieve a stable association.

Question 8

Which of the following best explains why sodium (Na) and chlorine (Cl) form sodium chloride (NaCl)?

Accepted Answer

Sodium transfers an electron to chlorine, resulting in a stable electron configuration for both.

Question 9

Which orbital is filled after the 1s orbital in an atom?

Accepted Answer

2s orbital

Question 10

A student claims that elements bond to increase their atomic number. Based on the study materials, how should you respond?

Accepted Answer

This is incorrect; elements bond to achieve a stable electron configuration, not to change their atomic number.

Question 11

Which of the following is NOT a characteristic of an element as described in the notes?

Accepted Answer

It can be broken down into simpler substances.

Question 12

Which of the following best describes the relationship between atoms and compounds?

Accepted Answer

Compounds are made of two or more elements in a fixed ratio.

Question 13

If an atom has a filled 1s orbital and a filled 2s orbital, how many electrons does it have?

Accepted Answer

4 (2 in 1s, 2 in 2s)

Question 14

Which of the following is a real-world example of a compound formed by a fixed ratio of elements?

Accepted Answer

Table salt ($$ \mathrm{NaCl} )$$

Question 15

What is the main reason elements share or transfer electrons when forming compounds?

Accepted Answer

To achieve a stable association by filling their outermost electron shell.

The Chemical Context of Life: Elements, Atoms, and Compounds

Study Guide - Practice Questions