Lesson 4. Flashcards
What is an atom?
An atom is the smallest particle of an element that still has its chemical properties.
What is a molecule?
A molecule is two or more atoms joined together. They are joined by attractive forces called chemical bonds.
Define “diatomic.”
A diatomic molecule is a molecule that consists of two atoms. Almost all diatomic molecules are gases at room temperature. An example includes oxygen.
Complete the sentence: the size of an atom is given by….
it’s atomic radius.
Define the term “bond length.”
The bond length is the distance between the centres of two joined atoms.
Atomic radii and bond lengths are typically around what value?
10^-10m.
Name the three subatomic particles and their place in the atom.
The three even smaller subatomic particles are:
• protons and neutrons, joined together as the nucleus at the centre.
• electrons, surrounding the nucleus in shells.
How much smaller is the radius of a nucleus than the radius of an atom?
100,000 times.
What is:
a) the relative mass.
b) the relative charge of a proton?
a) 1.
b) +1.
What is:
a) the relative mass.
b) the relative charge of a neutron?
a) 1.
b) 0.
What is:
a) the relative mass.
b) the relative charge of an electron?
a) 0.0005.
b) -1.
What does the term “relative” mean, and why are things “relative”?
When you compare quantities, they are relative to each other. Things, e.g. the masses of subatomic particles, are relative to avoid using overly small numbers.
