1. Use the images to get 6 keywords for todays lesson.
SAY WHAT YOU SEE!
Use the images to get 6 keywords for todays lesson. 1) 2) 3)
1000 kg
The best of these
NEUTRON
ION
PROTON 3) 4)
Radio image -
Exercise image -
Iron image -
Atom image -
Election image -
RADIOACTIVE
ELECTRON 6) 5)
…..
…..
MASS NUMBER
ATOMIC NUMBER

2. Learning objectives
Recall and detail the basic structure of an atom. (D)
Relate number of protons, electrons and neutrons to mass and atomic numbers. (C)
Explain how atoms form ions & identify the isotopes of different elements. (B)
Explain radioactivity in terms of alpha, beta and gamma radiation. (A)
Keywords:
Proton Ion
Neutron Isotope
Electron Mass number
Charge Atomic Number
NOTICES: …………….

3. What is the charge on an electron, proton and neutron?
What is an atom?
Draw and label an atom?
Electron
Proton
Neutron
Nucleus
What is in the Nucleus
What is the charge on an electron, proton and neutron?
Electron, - charge
Proton, + charge
Neutron, no charge

4. What is the mass of an atom?
What is an atom?
What is the mass of an atom?
Electron
Massproton = × 10-27 kilograms
Massneutron = 1.675×10−27 kilograms
Massneutron =9.10 × 10-31 kilograms
Protons and neutrons have the same mass, which is about 2,000 times larger than the mass of an electron.
These numbers being so small are not pratical to work with, so we use relative mass instead.
Nucleus
NOTE: When a nucleus binds it becomes more stable and therefore it must lose energy. At this level mass and energy are interchangeable so the mass of the nucleus is less than that of it's constituent parts. Carbon is used as it is pretty much exactly 12u for the nucleus. Oxygen doesn't actually have an atomic mass of 16, if you look at a periodic table with masses to several decimal places you will see this. I hope that's sufficient.
Sub-atomic Particle
Relative mass
Relative Charge
Proton +1
Neutron
Electron -1
Relative mass is used for atoms and is the mass of the atom relative the carbon-12. 1
Don’t worry for out physics we just need to know the relative mass of our sub-atomic particles 1
Almost zero

5. Reading the periodic table
atomic symbol
relative atomic mass
Name
atomic (proton) number
Key
Relative atomic mass
What is this number called?
Atomic (proton) number
What is this number called?
What is the relative atomic mass of:
Sodium?
Vanadium?
What is the atomic number of?
4) Chromium?
5) Strontium?
How many neutrons are there in?
6) Rubidium?
7) Hafnium?
8) Hydrogen? 23 51 24 38 48
106

6. Element Treasure Hunt Find the elements using the atomic number. Name
atomic symbol
relative atomic mass
Name
atomic (proton) number
Key
Atomic number 15.
Atomic number 51.
Atomic number 72.
Proton number 8.
Proton number 36.
Proton number 84.
Relative atomic mass 59.
Relative atomic mass 209.
Nitrogen
Antimony
Hafnium
Oxygen
Kryton
Polonium
Cobalt or Nickel
Bismuth or Polonium
The proton number is important to what the element is, the number of neutrons can vary for an element.

7. Ions What charge does an atom have? Can it become charged? Explain…
An atom has no overall charge as it has the same number of protons (+) and electrons (-).
Can it become charged? Explain…
Protons are tightly held in the nucleus but the electrons are not as tightly held and so a more able to be lossed or even gained. Gaining or losing electrons will change the overall charge of the atom. The charged particle formed is called an ion.
An ion is an atom or a molecule in which the total number of electrons is greater than the total number of protons, giving the atom or molecule a net positive or negative charge.

8. Ion or not an ion Is the atom shown an ion or not an ion? +1 EXAMPLE
Use the periodic table to identify it.
EXAMPLE
Hydrogen atom +1
An ion is an atom or a molecule in which the total number of electrons is greater than the total number of protons, giving the atom or molecule a net positive or negative charge.

9. Ion or not an ion Is the atom shown an ion or not an ion? +1
Use the periodic table to identify it.
Hydrogen ion (-) +1
An ion is an atom or a molecule in which the total number of electrons is greater than the total number of protons, giving the atom or molecule a net positive or negative charge.

10. Ion or not an ion Is the atom shown an ion or not an ion?
Use the periodic table to identify it.
Bromide ion (-)
+16
An ion is an atom or a molecule in which the total number of electrons is greater than the total number of protons, giving the atom or molecule a net positive or negative charge.

11. Ion or not an ion Is the atom shown an ion or not an ion? +9
Use the periodic table to identify it.
Fluorine ion (-) +9
An ion is an atom or a molecule in which the total number of electrons is greater than the total number of protons, giving the atom or molecule a net positive or negative charge.

12. Ion or not an ion Is the atom shown an ion or not an ion?
Use the periodic table to identify it.
Sodium ion (+)
+11
An ion is an atom or a molecule in which the total number of electrons is greater than the total number of protons, giving the atom or molecule a net positive or negative charge.

13. Ion or not an ion Is the atom shown an ion or not an ion?
Use the periodic table to identify it.
Magnesium ion (+2)
+12
An ion is an atom or a molecule in which the total number of electrons is greater than the total number of protons, giving the atom or molecule a net positive or negative charge.

14. Ion or not an ion Is the atom shown an ion or not an ion?
Use the periodic table to identify it.
Chlorine ion (-)
+17
An ion is an atom or a molecule in which the total number of electrons is greater than the total number of protons, giving the atom or molecule a net positive or negative charge.

15. Ion or not an ion Is the atom shown an ion or not an ion?
Use the periodic table to identify it.
Oxygen ion (-2)
An ion is an atom or a molecule in which the total number of electrons is greater than the total number of protons, giving the atom or molecule a net positive or negative charge.

16. Ion or not an ion Is the atom shown an ion or not an ion? Oxygen atom
Use the periodic table to identify it.
Oxygen atom
An ion is an atom or a molecule in which the total number of electrons is greater than the total number of protons, giving the atom or molecule a net positive or negative charge.

17. Ion or not an ion Is the atom shown an ion or not an ion?
Use the periodic table to identify it.
Aluminium ion (+3)
An ion is an atom or a molecule in which the total number of electrons is greater than the total number of protons, giving the atom or molecule a net positive or negative charge.

18. Ion or not an ion Is the atom shown an ion or not an ion? Calcium (+2)
Use the periodic table to identify it.
Calcium
(+2)
An ion is an atom or a molecule in which the total number of electrons is greater than the total number of protons, giving the atom or molecule a net positive or negative charge.

19. THEY ARE ISOTOPES OF THE CARBON ATOM12 C 6
Carbon 13 C 6
Carbon 14 C 6
What is different between these (above)?
The relative atomic mass number is varying but the atomic (proton) number remains the same – this means the number of neutrons varies.
All refer to a carbon atom.
THEY ARE ISOTOPES OF THE CARBON ATOM
Isotopes are atoms of the same element with different numbers of neutrons. The isotopes of an element have the same number of protons.

20. What are each of these isotopes of?
TASK – Isotopes of what?
What are each of these isotopes of? ? 6 3 ? 7 3 ? 8 3
Lithium - Li 1) = ? 35 17 ? 36 17 ? 37 17
chlorine - Cl 2) = ?
235 92 ?
236 92 ?
237 92
Uranium - U 3) =

21. Radioactivity What does it mean if something is radioactive?
If an atom is radioactive it means it emits (gives out) ionising radiation or particles.
Why would an atom be radioactive?
Proton (+)
Like charges repel, so how comes the protons are collected close together in the nucleus?
Electron
(-)
Neutron
(no charge)
Protons and neutrons are held together in the nucleus by strong nuclear forces, this ‘binding energy’ holds the nucleus together. When the binding energy is strong enough the nucleus is stable, when it is not the nucleus is unstable. Unstable atoms will lose mass and energy to become stable.

22. Radioactivity
How does an unstable nucleus lose mass and energy to become more stable?

23. Alpha Radiation - α
An alpha particle consists of 2 protons and 2 neutrons.
An alpha particles relative mass is 4 and relative charge is +2 α 4 2
By how much does relative mass number of the atom change?
Reduces by 4
Does anything else change?
Atomic number reduces by 2

24. β Beta Radiation - β Stays the same Does anything else change?
A beta particle consists of an electron emitted when a neutron in the nucleus turns into a proton.
A Beta particles relative mass is effectively 0 and relative charge is -1 β -1
By how much does relative mass number of the atom change?
Stays the same
Does anything else change?
Atomic number increase by 1

25. Gamma Radiation - γ
Gamma radiation is a high energy, high frequency wave.
Gamma radiation has no mass and no charge as it is wave.
By how much does relative mass number of the atom change?
No change
Does anything else change?
No change

26. LITERACY TASK
EXPLAIN IS AS MUCH DETAIL AS YOU CAN WHAT RADIOACTIVITY IS
KEY WORDS TO USE:
Atom Proton Alpha
Isotope - Neutron - Beta
Unstable Electron - Gamma
Stable Energy Mass