Atoms

Question 1

What Are Atoms?

Answer 1

~ Atoms are the basic building blocks of all materials.

Question 2

Element

Answer 2

~ An element is a substance made up of only one type of atom.

Question 3

Molecules

Answer 3

~ A molecule is formed when two or more atoms join (bond) together chemically.

Question 4

Compound

Answer 4

~ When a molecule is made up of two or more different types of elements chemically combined, we call it a compound.

Question 5

Structure of The Atom

Answer 5

~ The atom is made up of smaller particles called sub-atomic particles.
These are:
~ Protons ~ Neutrons ~ Electrons

Question 6

Atomic And Mass Number

Answer 6

Atomic Number:
~The atomic number tells you how many protons (which
is the same as the number of electrons) there are in one atom of the element.

Mass Number:
~The mass number tells you how many protons and neutrons
there are in the atom.

Question 7

The Modern Periodic Table

Answer 7

~ Vertical columns, called groups, in which the elements with similar physical and chemical
properties (behaviours) are grouped together
~ Horizontal rows, called periods, which are in order of increasing proton number.

Question 8

The Alkali Metals

Answer 8

~ All the alkali metals have one electron in their outer shell. The atoms ‘want’ to get rid of this
loose electron. As a result, the alkali metals are very reactive and behave similarly.

Question 9

Group 2

Answer 9

~Alkaline Earth Metals
~ Elements in this group include:
• Beryllium (Be)
• Magnesium (Mg)
• Calcium (Ca).
All elements in this group have two electrons in their outer shell.

Question 10

Group 7

Answer 10

~ Halogens
~ The elements in group 7 have seven electrons in their
atom’s outer shell.
~ Fluorine (F)
~ Chlorine (Cl)

Question 11

Group 8 ( Group 0)

Answer 11

~ The Noble Gases
~ The elements in group 8 are all gases and have full outer
shells of electrons in their atoms.
• Helium (He)
• Neon (Ne)
• Argon (Ar), which is used in filament lamps (light bulbs).

Question 12

What Are Ions?

Answer 12

~ When atoms lose or gain electrons they become charged particles and are called ions.

(• Group 1 - alkali metals. These have only one electron in the outer shell, which they lose to form
a positive ion (+1), e.g. Na”’,
> Group 2 - alkaline earth metals. These have two electrons in their outer shell so will lose two
electrons to form a positive ion (+2), e.g. Mgtz.
Group 6 - non-metals. These have six electrons in their outer shell and so will gain two
electrons for a full outer shell to form a negative ion (-2), e.g. 0-2,
Group 7- halogens. These have seven electrons in their outer shell and so will gain one
electron to form a negative ion (-1), e.g. Cl1.)

Question 13

How Are Chemical Bonds Formed?

Answer 13

~ A compound forms when two different elements chemically combine.

Question 14

Ionic Bonds

Answer 14

~ lonic bonding produces a compound that is formed from a metal and a non-metal and is
made up of ions. This occurs when one atom loses electrons and another atom gains electrons.

Question 15

Covalent Bonding

Answer 15

~ Covalent bonding produces a compound formed from
non-metals in which each atom shares electrons with
another atom.

Question 16

Chemical Formulas

Answer 16

~ Every compound has a formula - it tells you the type and number of atoms present in a
compound. The chemical formula is made up of letters and numbers

Question 17

Combining Metals And Non-Metals

Answer 17

~ When a metal and a non-metal are combined, the resultant compound is called after the
name of the metal followed by the name of the non-metal, with its ending changed to “-ide?
For example:
sodium + chlorine = sodium chloride
Metal Non-metal Compound

Question 18

Combining Metal Atoms, Non-Metal Atoms And Oxygen

Answer 18

~ When naming compounds formed by combining a metal atom, a non-metal atom and oxygen, the name of the metal comes first, the name of the non-metal comes next and the ending is’-ate’