Atoms

Question 1

What is the atomic mass of an element?

Answer 1

The atomic mass of an element is the weighted average mass of the isotopes of that element, measured in atomic mass units (amu).

Question 2

How many protons does a hydrogen atom have?

Answer 2

A hydrogen atom has 1 proton.

Question 3

True or False: Neutrons have a positive charge.

Answer 3

False: Neutrons have no charge.

Question 4

Which subatomic particle determines the identity of an element?

Answer 4

Protons determine the identity of an element.

Question 5

Fill in the blank: The number of neutrons in an atom can be calculated by subtracting the atomic number from the _____ number.

Answer 5

mass

Question 6

What is the charge of an electron?

Answer 6

An electron has a negative charge.

Question 7

What is the periodic table?

Answer 7

The periodic table is a tabular arrangement of the chemical elements, organized by increasing atomic number.

Question 8

How many electrons can the first energy level hold?

Answer 8

The first energy level can hold a maximum of 2 electrons.

Question 9

True or False: The atomic number is the total number of protons and neutrons in an atom.

Answer 9

False: The atomic number is the number of protons only.

Question 10

What is an isotope?

Answer 10

variant of a chemical element that has the same number of protons but a different number of neutrons

Question 11

Which element has the atomic number 6?

Answer 11

Carbon has the atomic number 6.

Question 12

Fill in the blank: The mass number of an atom is the sum of its _____ and _____ counts.

Answer 12

proton, neutron

Question 13

What does the term ‘valence electrons’ refer to?

Answer 13

Valence electrons are the electrons in the outermost shell of an atom that are involved in chemical bonding.

Question 14

True or False: All elements have isotopes.

Answer 14

True: Most elements have one or more isotopes.

Question 15

What is the chemical symbol for gold?

Answer 15

The chemical symbol for gold is Au.

Question 16

Which part of the atom has the largest mass?

Answer 16

The nucleus, which contains protons and neutrons, has the largest mass.

Question 17

What are the three main subatomic particles?

Answer 17

The three main subatomic particles are protons, neutrons, and electrons.

Question 18

Fill in the blank: The periodic table is organized into _____ and periods.

Answer 18

groups

Question 19

True or False: Electrons are found in the nucleus of an atom.

Answer 19

False: Electrons are found in electron shells outside the nucleus.

Question 20

What is the primary purpose of the periodic table?

Answer 20

to organize elements based on their atomic number and properties.

Question 21

How many neutrons are in a carbon-14 atom?

Answer 21

A carbon-14 atom has 8 neutrons.

Question 22

What determines the chemical behavior of an element?

Answer 22

number of valence electrons

Question 23

Fill in the blank: The elements in the same group of the periodic table have similar _____ properties.

Answer 23

chemical

Question 24

What is the mass of a proton?

Answer 24

The mass of a proton is approximately 1 amu.

Question 25

True or False: The atomic mass is always a whole number.

Answer 25

False: The atomic mass is often a decimal due to the averaging of isotopes.

Question 26

What is the electron configuration of oxygen?

Answer 26

1s² 2s² 2p⁴.

Question 27

Which element has the highest atomic number?

Answer 27

Oganesson (Og) has the highest atomic number, 118.

Question 28

Fill in the blank: The _____ of an element is unique to that element and is represented by its atomic number.

Answer 28

number of protons

Question 29

What is the main difference between metals and nonmetals?

Answer 29

Metals are typically good conductors of heat and electricity, while nonmetals are poor conductors.

Question 30

True or False: The atomic mass unit (amu) is based on the mass of a carbon-12 atom.

Answer 30

True: The amu is defined relative to the carbon-12 isotope.

Question 31

What is the chemical symbol for sodium?

Answer 31

The chemical symbol for sodium is Na.

Question 32

How does the number of protons relate to the atomic number?

Answer 32

The atomic number is equal to the number of protons in an atom.

Question 33

Fill in the blank: Elements in the same _____ have the same number of valence electrons.

Answer 33

group

Question 34

What is the significance of the periodic law?

Answer 34

The periodic law states that the properties of elements are periodic functions of their atomic numbers.

Question 35

Which subatomic particle has the least mass?

Answer 35

Electrons have the least mass of the three subatomic particles.

Question 36

True or False: The number of electrons in a neutral atom is equal to the number of protons.

Answer 36

True: In a neutral atom, the number of electrons equals the number of protons.

Question 37

What element is represented by the symbol 'Cl'?

Answer 37

Chlorine is represented by the symbol 'Cl'.

Question 38

What is the process of gaining or losing electrons called?

Answer 38

The process of gaining or losing electrons is called ionization.

Question 39

What is an atom?

Answer 39

The smallest unit of matter that retains the properties of an element.

Question 40

# think of +, - , 0 What do atoms consist of?

Answer 40

a nucleus surrounded by electrons. | a nucleus is protons + neutrons

Question 41

What is an ion?

Answer 41

An atom or molecule with a net electric charge due to the loss / gain of electrons.

Question 42

Why is an atom electrically neutral?

Answer 42

because it has an equal number of protons & electrons