Atoms

Question 1

Describe the structure of an atom?

Answer 1

It has a small nucleus that contains protons and neutrons.
Electrons move around the nucleus.

Question 2

Describe the differences between protons, neutrons and electrons?

Answer 2

Protons are positively charged. (+1)
Neutrons have no charge. (neutral)
So the nucleus has a positive charge.
Electrons are negatively charged.(-1)
The number of protons always equal the number of electrons in an atom so the over all charge is always neutral.

Question 3

What are isotopes?

Answer 3

The term isotope is derived from the Greek roots isos (ἴσος “equal”) and topos (τόπος “place”), meaning “the same place”

Isotopes. are atoms with the same atomic number but a different mass number.
They have the same number of protons but a different number of neutrons.

Isotopes are distinct nuclear species (or nuclides) of the same chemical element. They have the same atomic number (number of protons in their nuclei) and position in the periodic table (and hence belong to the same chemical element), but different nucleon numbers (mass numbers) due to different numbers of neutrons in their nuclei. While all isotopes of a given element have similar chemical properties, they have different atomic masses and physical properties.[1]

Question 4

What is relative atomic mass?

Answer 4

the average mass of atoms of an element relative to the mass of an atom of carbon-12 (which is given a mass exactly of 12).

Carbon is used as the standard to which the relative masses of other elements are compared and it has a relative atomic mass of 12.

Question 5

What is relative atomic mass?

Answer 5

the average mass of atoms of an element relative to the mass of an atom of carbon-12 (which is given a mass exactly of 12).

Carbon is used as the standard to which the relative masses of other elements are compared.

Question 6

What are compounds?

Answer 6

A compound is a pure substance that is made from more than one element. In a compound, elements are chemically bonded together, which makes it very difficult to separate them.
When a compound is made, the atoms of the elements bond together in a fixed
ratio
. This means that each compound can be represented by a chemical formula.
For example, the
formula
of water is H₂O and the formula of carbon dioxide is CO₂.

Question 7

What is a chemical bond?

Answer 7

Bonds involve atoms giving away, taking or sharing electrons.

Question 8

What is a mixture?

Answer 8

A mixture is formed when two or more elements or compounds are present without being chemically bonded together.

the two ingredients can be separated using physical processes, without chemical reactions. This is because they are not chemically bonded together.
Here are some examples:

A mixture of sand and water can be separated using
filtration
.
A solution of salt and water can be separated using
crystallisation
or distillation
.
A mixture of iron filings and sulfur powder can be separated using a magnet