3 Atomic Structure

Question 1

How many elements are in the periodic table of elements

Answer 1

118 elements

Question 2

Define “Atom”

Answer 2

The smallest piece of an element that can still be recognised as that element

Question 3

Define “Molecule”

Answer 3

A molecule is the smallest particle of a substance that can exist on its own and still keep the substance’s chemical properties.

Question 4

Define “Atomic number”/”Proton number”

Answer 4

The total number of protons in an atom

Question 5

Define “Mass number”/”nucleon number” (equation)

Answer 5

The mass (nucleon) number is the total number of protons and neutrons in an atom’s nucleus.
Mass number=number of protons + number of neutrons

Question 6

Define “Isotopes”

Answer 6

Isotopes are atoms of the same element with the same atomic number but different mass numbers.

Question 7

Define “Protons” (Relative mass & charge)

Answer 7

A positively charged sub-atomic particle with a relative mass of 1 and a relative charge of +1

Question 8

Define “Neutrons” (Relative mass & charge)

Answer 8

A neutrally charged sub-atomic particle with a relative mass of 1 and a relative charge of 0

Question 9

Define “Electrons” (Relative mass & charge)

Answer 9

A negatively charged sub-atomic particle with a relative mass of 1/1836 and a relative charge of -1

Question 10

Define “Sub-atomic particles”

Answer 10

Particles that make up an atom consisting of electrons, protons and neutrons

Question 11

Define the structure of an atom

Answer 11

An atom has a central nucleus containing protons and neutrons, with electrons arranged in shells around the nucleus.

Question 12

how do you work out the number of neutrons

Answer 12

Number of neutrons=Mass number−Atomic number

Question 13

how are elements and their info showed on the periodic table

Answer 13

On the periodic table, each element is shown by its Relative atomic mass (top), chemical symbol (middle), and atomic number (bottom).

Question 14

Define “relative atomic mass”

Answer 14

Relative atomic mass is the weighted average mass of an element’s isotopes compared to 1/12 of the mass of a carbon-12 atom.

Question 15

How do you work out the “relative atomic mass”?

Answer 15

-Multiply each isotope’s mass number by its percentage abundance
-Add the results
-Divide by 100

Question 16

Number of electrons is equal to…

Answer 16

Number of electrons = atomic number

Question 17

Number of protons is equal to…

Answer 17

Number of protons = atomic number

Question 18

Number of neutrons is equal to…

Answer 18

Neutrons = mass number − atomic number

Question 19

How is the periodic table of elements arranged

Answer 19

The periodic table is arranged in order of increasing atomic number, with elements in rows (periods) and columns (groups).

Question 20

the smallest number displayed with an element is always the…

Answer 20

The smallest number displayed with an element is always the atomic number.

Question 21

why are the number of protons in an atom always equal to the number of electrons

Answer 21

In a neutral atom, the number of protons equals the number of electrons so the atom has no overall charge.

Question 22

Define “The periodic table”

Answer 22

The periodic table is a chart of all known elements arranged in order of increasing atomic number, showing repeating patterns in their properties.

Question 23

define groups and periods on the periodic table

Answer 23

Groups: elements in a column that have similar chemical properties and show a trend in physical properties
Periods: elements in a row that exhibit a trend in chemical and physical properties

Question 24

define “Energy level”/”Electron Shells”

Answer 24

This is where electrons are found in the atom

Question 25

Define "Electronic configuration" and how to work it out

Answer 25

Electronic configuration is the arrangement of electrons in shells (energy levels) around the nucleus of an atom. Find the atomic number → this equals the number of electrons (for a neutral atom). Fill the electron shells:

Question 26

describe how the energy levels are different between atoms shells

Answer 26

Electron shells further from the nucleus have higher energy than inner shells.

Question 27

what elements have the same numbers of electrons in their outer shells

Answer 27

Elements that have the same number of electrons in their outer shells are found in the same group (column) of the periodic table.

Question 28

the numbers of electrons in the outer shells are the same as...

Answer 28

The number of electrons in the outer shell is the same as the group number

Question 29

the period number gives the number of...

Answer 29

The period number gives the number of electron shells.

Question 30

what does the reaction of atoms depend on (why)

Answer 30

The reactivity of atoms depends on their outer-shell electrons because reactions involve gaining, losing, or sharing these electrons to achieve a full outer shell.

Question 31

what elements contain similar properties (why/Example)

Answer 31

Elements that have similar properties are found in the same group (column) of the periodic table. this is because they have the same number of electrons in their outer shells giving them similar chemical reactions (Example: Group 1 (Alkali metals) are all very reactive metals)

Question 32

what are the "noble gases" and why are they so unreactive

Answer 32

The noble gases are the elements in Group 0 of the periodic table they are so unreactive because they have a full outer electron shell this makes them very stable and do not easily gain or lose electrons

Question 33

where do you find the metals and non-metals in the periodic table

Answer 33

Metals are found on the left-hand side and centre of the periodic table. Non-metals are found on the right-hand side of the periodic table.

Question 34

Define properties of Metals (5)

Answer 34

-Good conductors of heat and electricity -Shiny -Malleable -Usually have high melting and boiling points -Tend to lose electrons in chemical reactions

Question 35

Define properties of non-metals (5)

Answer 35

-Poor conductors of heat and electricity -Dull -Brittle when solid -Low melting and boiling points -Tend to gain electrons in chemical reactions

Question 36

Define "Metals" and "non-metals"

Answer 36

metals: A substance that exhibits metallic properties such as conductance of both electricity and heat non-metals: A substance that exhibits non-metallic properties such as poor conductance of both electricity and heat

Question 37

name the 6 main scientists who contributed to the discovery of the atom

Answer 37

- Ancient Greek - Dalton - JJ Thomson - Rutherford - Bohr - Schrödinger

Question 38

How did Ancient Greek contribute to the discovery of the atom

Answer 38

Ancient Greek philosophers, such as Democritus, first suggested that matter is made of tiny indivisible particles called atoms.

Question 39

How did Dalton contribute to the discovery of the atom

Answer 39

Dalton proposed the first atomic theory, stating that matter is made of atoms which combine in fixed ratios.

Question 40

How did JJ Thomson contribute to the discovery of the atom

Answer 40

J. J. Thomson discovered the electron and proposed the plum pudding model of the atom.

Question 41

How did Rutherford contribute to the discovery of the atom

Answer 41

Rutherford discovered that atoms have a small, dense, positively charged nucleus through the gold foil experiment.

Question 42

How did Bohr contribute to the discovery of the atom

Answer 42

Bohr proposed that electrons move around the nucleus in fixed energy levels, explaining atomic spectra.

Question 43

How did Schrödinger contribute to the discovery of the atom

Answer 43

Schrödinger showed that electrons exist in probability regions around the nucleus rather than fixed orbits, leading to the electron cloud model of the atom.

Question 44

Define "The step"

Answer 44

A line in the periodic table that separates the metals from the non-metals elements bordering this line are often referred to as Metalloids

Question 45

Define "Metalloids"

Answer 45

Elements found boarding the "Step" these elements have metallic and non-metallic properties

Question 46

Define "Physical properties" and "Chemical properties"

Answer 46

Physical properties: Features of a substance that can be observed without changing the substance itself Chemical properties: Features of the way a substance reacts with other substances

Question 47

Define "Atomic mass"

Answer 47

The total number of protons and neutrons

Question 48

What are scientific models and why do we use them

Answer 48

Scientific models are simplified representations used to explain, visualise, and predict scientific ideas when the real thing is difficult to study directly.

Question 49

Define "compounds"

Answer 49

A compound is a substance formed when two or more different elements are chemically bonded.

Question 50

Define what happens if an Atom looses or gains an electron

Answer 50

Loses electrons → becomes a positive ion Gains electrons → becomes a negative ion