Topic 1 - Atomic Structure And The Periodic Table Flashcards
Mass and charge of the particles
Proton, 1, +1
Neutron, 1, 0
Electron, very small (1/1838), -1
What makes an ion different to an atom
The number of electrons are different to the number of protons
How big is an atom
0.1 nanometers
What determines the size of the atom?
The volume of orbit of the electrons
What is an element
This is a substance made up of atoms that all have the same number of protons in their nucleus
Out of the three particles, which one determines what atom it is?
The number of protons in the nucleus
If the neutrons or electron number changes, it is still the same atom
What makes an isotope?
What changes in the atomic and mass numbers?
Different forms of the same element with a different number of electrons
Same atomic number, different mass number
Name two common isotopes
Carbon - 12
Carbon - 13
Why is the relative atom mass used instead of the mass number when referring to an element as a whole
Because many elements can exist as a number of different isotopes
What is the relative atomic mass formula
Relative atomic mass =
Sum of (isotope abundance X isotope mass number)
____________________________________
Sum of abundance of all isotopes
When is a compound formed
When elements react with other elements
What is a compound
A substance formed from 2 or more elements
What holds compounds together
Chemical bonds
What are the three ways bonds are made
By giving away, taking or sharing electrons
What is required in ionic, covalent and metallic bonding
Metals and non metals
Ionic: metal + non-metal
Covalent: non-metal + non-metal
Metallic: metal + metal
What happens in ionic bonding (electron wise)
Metal atoms lose electrons and non metals gain electrons
Why are there strong bonds in ionic bonding?
Because the opposite charges (the positive of the metal and the negative of the non-metal) means they are strongly attracted to each other.
What happens in covalent bonding (electron wise)
The electrons are shared
What are the ways of showing chemical equations
Word equations Symbol equations (need to be balanced)
Whats the difference between a mixture and a compound
Mixtures are not chemically bounded
What is the goal of atoms
To have full shells (also known as energy levels)
What similarities do the elements in a period have
The same number of outer shells
What similarities do the elements in a group have
They have the same amount electrons on their outer shell
GROUP 0 are an exception to this (Helium has two and Neon has 8)
What is the difference between groups and periods have in the periodic table
Groups are vertically down
Columns are horizontal
Why do non metals have a hard time forming positive ions
They are generally near the top:
So they are closer to the nucleus, and therefore feel a stronger attraction
and far right of the periodic table:
So the have more electrons to lose (e.g) group 7 have to lose 7
Different physical properties of metals and non metals
Metals: Metallic bonding Strong Good at conducting heat and electricity Have high boiling and melting points
Non-metals:
Dull looking
Aren’t always solid at room temperatures
Don’t generally conduct heat or electricity
Have a lower density
Factors of the group 1 metals
Also known as the Alkali metals
One electron so very reactive
Soft and low density
Lower melting and boiling points the lower you go
Reactivity of group 1
More reactive the further down you go
The outer electron is easier to lose the further down you go as it is further away from the attraction o pf the nucleus
What happens to group 1 metals when the react with
A)water
B)chlorine
C)oxygen
A)produce hydrogen gas They react vigorously Lithium, Sodium and Potassium float, move and fizz Also makes the water alkaline B)produce salt called METAL CHLORIDE Again react vigorously C) from a METAL OXIDE
Factors of group 7
The halogens
Non metals
Must be in pairs of 2
Most poisonous
Higher boiling and melting points the further you go down
Reactivity of group 7
As you go down, it gets less reactive
This is because its harder to gain an extra electron as it is further from the attraction of the nucleus
What happens when two halogens (elements in group 7) react
The more reactive halogen will displace (remove) the less reactive one.
Eg chlorine will displace iodine
Eg Cl2 + 2Kl = I2 + 2KCL
What must all gases except for the noble gases do and why
They must all travel in pairs as this gives them a full outer shell
Eg Oxygen
E.g O2
Features of the noble gases (group 0)
All colourless gas at room temperature
Non-flammable
Full outer shells already
What are the pattern of boiling points for group 7/the noble gases
The boiling point increases as you move down
This is because there are more electrons, so more bonds are needed to be broken
How would you guess what state a noble gas is in
Eg Neon is a gas at 25 degrees. Predict what state helium is at this temperature
The further down you go, the higher the boiling point becomes
As neon is further down the group than helium, it must have a higher boiling point
Therefore, helium would be a gas at 25 degrees
