THE HISTORY OF ATOMIC CHEMISTRY
1. WATCH this clip
2. IDENTIFY 2 pieces of technology that has contributed to our understanding of the atom.
2. IDENTIFY 2 pieces of technology that has contributed to our understanding of the atom.
AFTER WATCHING THIS CLIP IDENTIFY AND RECORD AT LEAST 2 TECHNOLOGIES THAT HAVE ADVANCED OUR UNDERSTANDING OF ATOMS.
ATOMIC STRUCTURE
All substances are made from tiny particles called atoms.
An atom has a small central nucleus made up of smaller sub-atomic particles called protons and neutrons.
The nucleus is surrounded by even smaller sub-atomic particles called electrons.
Protons and electrons have an electrical charge.
Protons are positive, electrons are negative. Neutrons are neutral.
An atom has a small central nucleus made up of smaller sub-atomic particles called protons and neutrons.
The nucleus is surrounded by even smaller sub-atomic particles called electrons.
Protons and electrons have an electrical charge.
Protons are positive, electrons are negative. Neutrons are neutral.
ATOMIC NUMBER
- The atomic number of an atom is the number of protons it contains.
- The atoms of different elements have different numbers of protons.
- For example, all oxygen atoms have 8 protons and all sodium atoms have 11 protons.
The atomic number of a chemical element tells us the number of protons in the nucleus of an atom of that element, which uniquely identifies the element. It determines the element's place in the periodic table and its chemical properties, as the number of protons also determines the number of electrons in a neutral atom of the element.
- The atoms of different elements have different numbers of protons.
- For example, all oxygen atoms have 8 protons and all sodium atoms have 11 protons.
The atomic number of a chemical element tells us the number of protons in the nucleus of an atom of that element, which uniquely identifies the element. It determines the element's place in the periodic table and its chemical properties, as the number of protons also determines the number of electrons in a neutral atom of the element.
ATOMIC MASS
- The atomic mass of an atom is the total number of protons and neutrons it contains.
CALCULATING NUMBERS OF SUBATOMIC PARTICLES
The symbol for an atom can be written to show its mass number at the top, and its atomic number at the bottom.
To calculate the numbers of subatomic particles in an atom, use its atomic number and mass number:
To calculate the numbers of subatomic particles in an atom, use its atomic number and mass number:
- number of protons = atomic number
- number of electrons = atomic number
- number of neutrons = mass number - atomic number
THE ROLE OF SUBATOMIC PARTICLES
This table reinforces what you have already learnt about the charge and calculating the numbers of subatomic particles but you should also have an idea of the role of these.