Atomic Structure and the periodic table Flashcards
What is an atom?
The smallest part of an element that can exist
What is a chemical formula used for?
To represent an element or compound in balanced chemical equations
What is a compound?
A substance that contains two or more elements that are chemically combined
What is an ion?
It is a charged particle formed when an atom, or a group of atoms, loses or gains electrons.
What is a word equation?
Represents a chemical reaction using the names of the substances involved.
What does the arrow in a word equation mean?
Reacts to make
Name the 4 state symbols?
- (s) solid
- (l) liquid
- (g) gas
- (aq) Aqueous Solution
What do the total mass of the products equal?
The total mass of the reactants
What is in the centre of a atom and what is is surround it by?
Nucleus
Surrounded by elections arranged in shells
What is the relative mass and charge of a proton?
1 , +1
What is the relative mass and charge of a neutron?
1, 0
What is the relative mass and charge of a electron?
Very Small, -1
What are protons charge?
Positive
What are Neutrons charge?
Neutral
What is the atomic number?
The number of protons in an atom of an element.
What does an atom contain?
Equal number of protons and electrons
What is the Mass Number?
The mass number of an atom is its total number of protons and neutrons.
How do you calculate the number of protons, neutrons and electrons in an atom?
- Number of protons = atomic number
- Number of electrons = atomic number
- Number of neutrons = mass number - atomic number
What is an isotope?
Atoms of an element with the same number of protons and electrons but different number of neutrons.
(The same Atomic Number, Different Mass Number)
What was the name of the Russian scientist who developed a periodic table?
Dmitri Mendeleev
How did he arrange his periodic table and what did he leave spaces for?
- Arranged elements in order of atomic mass
- Left gaps for elements that had not been discovered
What is the difference with the modern periodic table?
- Elements are arranged in order of atomic number (number of protons)
- Group 0 was not fully discovered at the time
What are the gases in Group 0 called?
Noble Gases
How reactive are the gases in Group 0?
Very Unreactive
Why are Group 0 so nonreactive?
They have a full outer shell of electrons
What is the boiling point of group 0 gases like?
All below 0, vary as you go down the group.
Which side(s) of the periodic table are the metals?
Left and Centre
What are the central metals called?
Transition metals
What happens when metal atoms react?
They lose their outer electrons and achieve a full outer shell
What do metals always form?
Positive Ions
What are group 1 metals called?
Alkaline Metals
What do all group 1 metals have in their outer shell?
All have 1 electron
How reactive are group 1 metals?
Very Reactive ( more reactive as you go down the group)
Why are group 1 metals more reactive as they go down the group?
The outer electron is less attracted to the nucleus and easier to lose.
