Topic 1- Key Concepts In Chemistry 📄

Question 1

What is an atom?

Answer 1

Smallest unit of matter

Question 2

What is an element?

Answer 2

Single type of atom

Question 3

What is a compound?

Answer 3

2 or more elements chemically bonded together

Question 4

What is a mixture?

Answer 4

2 or more elements or compounds not chemically bonded

Question 5

What is a chemical formula?

Answer 5

Shows the numbers of each type of atom in a compound

Question 6

What is the periodic table?

Answer 6

The table of elements in which all the elements we know are in order of atomic number

Question 7

Sub-Atomic Particles
What charge does an electron have?

Answer 7

Negative (-1)

Question 8

Sub-Atomic Particles
What charge does a proton have?

Answer 8

Positive (+1)

Question 9

Sub-Atomic Particles
What charge does a neutron have?

Answer 9

Neutral (0)

Question 10

Sub-Atomic Particles
What is the relative mass of an electron?

Answer 10

0 or

1
——
1840

Question 11

Sub-Atomic Particles
What is the relative mass of a proton?

Answer 11

1

Question 12

Sub-Atomic Particles
What is the relative mass of a neutron?

Answer 12

1

Question 13

What is in the nucleus of an atom?

Answer 13

Protons and Neutrons

Question 14

What is found outside the nucleus & how?

Answer 14

Electrons in shells

Question 15

Why does an atom have no overall charge?

Answer 15

Because it contains the same number of electrons (-1) and protons (+1)

Question 16

What is the atomic number?

Answer 16

The number of protons (equal to the number is electrons) in an atom

Question 17

How do you identify the atomic number?

Answer 17

It is the smaller number

Question 18

What is the relative atomic mass?

Answer 18

The number of protons and the number of neutrons

Question 19

How do you identify the relative atomic mass?

Answer 19

It is the higher number

Question 20

How do you find the number of neutrons?

Answer 20

Neutrons= Relative atomic mass - Atomic number

Question 21

What do you know about the periodic table? (7)

Answer 21

1. Split into periods ( number of electron shells) and groups ( how many electrons are in the outer shell)
2. Metals and NON+Metals
3. Organised by increasing atomic number
4. Includes atomic and relative mass Number
5. It contains 118 elements
6. Includes symbols
7. Dmitri Mendeleev

Question 22

Where is most of the mass of an atoms found in the atom?

Answer 22

In the nucleus of the atom because protons and neutrons have a relative mass of 1 whereas electrons have a relative mass of 0 so the electrons shells don’t contribute to the overall mass

Question 23

What is an isotope?

Answer 23

** Atoms of an element that have the same number of protons, but different numbers of neutrons in their nuclei. **
This results in a different atomic mass, but the same mass number

Question 24

Isotopes of an element have: (2)

Answer 24

> Same atomic number
Different mass numbers

Question 25

How do you calculate Relative atomic mass?

Answer 25

(Mass number of isotope 1 X percentage abundance of isotope 1) + (Mass number of isotope 2 X percentage abundance of isotope 2)
———————————————
100

Question 26

What do columns represents on the periodic table?

Answer 26

Groups

Question 27

What does the group number show on the periodic table table?

Answer 27

The number of electrons in the outer shell of an atom
—> therefore similar chemical properties

Question 28

Group =

Answer 28

Column

Question 29

Period =

Answer 29

Row

Question 30

What does the period tell you on the periodic table?

Answer 30

How many electron shells are in an atom

Question 31

How do electrons link to the position of an atom on the Periodic Table?

Answer 31

The links are: the number of circles in the electronic configuration of an element is represented in the periodic table as the period number that element is situated in. the number of electrons in the outermost shell of an element is represented in the periodic table as the group number that element is situated in.

Question 32

How to identify metals and non-metals on the periodic table?

Answer 32

Metals are located on the left of the periodic table, and nonmetals are located on the upper right. They are separated by a diagonal band of semi metals.

Question 33

Properties of metals:

Answer 33

Most metals share similar properties with each other. For example:
They have high melting and boiling points
meaning they are solid at room temperature
They are good
conductors
of heat and electricity
They are shiny in their appearance
They are malleable
Have a high density
They are sonorous

Question 34

Properties of non-metals:

Answer 34

Poor conductors of heat and electricity
Dull in their appearance
Weak and brittle
Generally low melting and boiling points, meaning they are gases and liquids at room temperature
Not sonorous

Question 35

Who was Dmitri Mendeleev ?

Answer 35

Creator of the first periodic table

Question 36

How did dmitri mendeleev group elements?

Answer 36

According to their properties

Question 37

What did Mendeleev do with the periodic table?

Answer 37

Left gaps where he thought new elements might be discovered would fit

Question 38

How do we organise the periodic table?

Answer 38

By increasing atomic number

Question 39

What is electronic configuration?

Answer 39

The number of electrons that go into each wheel of an atom

Question 40

How are electrons arranged?

Answer 40

In shells around the nucleus of an atom

Question 41

How many electrons in the
1st
2nd
3rd
4th
Shell of an atom?

Answer 41

Max 2
Max 8
Max 8
Max 18