Atoms and molecules

Question 1

What is an atom?

Answer 1

• All matter is made up of tiny particles called atoms
• Atoms are made up of even smaller subatomic particles
• Atoms are mostly empty spaced
• The mass comes from the Protons and Neutrons in the nucleus of the atom.

Question 2

What are the parts of an atom?

Answer 2

The parts of an atom are protons, neutrons, and electrons

Question 3

Protons

Answer 3

• Positively charged particles in the nucleus of an atom

- Mass- 1 AMU

Question 4

What determines the element of an atom?

Answer 4

The number of protons determines the element of an atom.

Question 5

Electron

Answer 5

• negatively charged particles in the atoms Shell, level or orbital.
• The mass of an electron is 1/1850 to the one of a proton, so it does not add significant mass to the atom.

Question 6

Neutrons

Answer 6

• Neutral particles in the nucleus of an atom

- They have no charge and have a mass of one AMU

Question 7

Hydrogen

Answer 7

Hydrogen is the only element that does not have at least one neutron in its nucleus.

Question 8

What is Dalton’s atomic theory?

Answer 8

• Dalton’s Atomic theory is a scientific theory about atoms.
• The idea of atoms was already known at the time, but not widely accepted.
• Dalton’s theory of atoms was based on actual observations
• Before this, ideas of atoms were based more on philosophy

Question 9

What did Dalton discover about atoms?

Answer 9

1. Elements are made of extremely small particles called atoms
2. Atoms of a given element are identical in size, mass and other properties; atoms of different elements differ in size, mass and other properties
3. Atoms cannot be subdivided, created or destroyed.
4. Atoms of different elements combine in simple whole-number ratios to form chemical compounds
5. In chemical reactions, atoms are combined, separated or rearranged.

Question 10

What are atoms and matter?

Answer 10

• Matter can be described as any entity that has weight and mass and occupies space.
• Matter is found in 1 of three states: solid, liquid or gas
• An atom is a particle that is the most basic unit of matter
• Any substances, whether solid, liquid or gas, is made up of millions of tiny particles
• Composed of subatomic particles: protons, electrons & neutrons

Question 11

What is a molecule?

Answer 11

• When two or more atoms combine they give rise to a molecule.
• A molecule can be made up of atoms of the same element

-For example oxygen atoms combining to for O2
Or various atoms of different elements combining, example water

-Two hydrogen (H2) atoms combine with one oxygen atom to form water (H2O)