Atoms,element and compounds

Question 1

What is an element?

Answer 1

Elements are simple substances. They cannot be split into smaller ones by chemical reactions. The particles that make up an element are called atoms. Each element is made from the same kind of atoms.

Question 2

What is an atom?

Answer 2

An atom is the smallest part of an element that can exist. Atoms are made from 3 types of subatomic particles.

Question 3

What makes up nucleons?

Answer 3

Protons (p+)
Neutrons (n0)
Electrons (e-)

Question 4

What are the 3 particles reltive charge and mass?

Answer 4

Protons: relative mass +1, relative charge 1
Neutrons: relative mass 0, relative charge 1
Electrons: relative mass -1, relative charge 1/2000

Question 5

What is the radius of an atom and the radius of a nucleus?

Answer 5

Radius of an atom = 0.1nm (1x10-10m)

Radius of a nucleus = 1/10000 that of an atom (1x10-14m)

Question 6

What is the difference between a compound and mixture?

Answer 6

Compounds have a fixed composition whereas mixture have no fixed composition.
Chemical reactions must be used to separate the element in a compound whereas the different elements or compounds in a mixture can be separated can be separated again more easily.
There are chemical bonds between the atoms of the different elements in the compound.