Energy Light Energy Essay

Submitted By exoticbabyshawol
Words: 1872
Pages: 8

P1: Periodic Table


Lithium is in group 1. Group 1 metals are called alkali metal. They have an electron configuration of 1s2, 2s1 in order to satisfy the octet rule. It has one electron in its outer shell. Therefore, its position is in group 1.

2. Sodium: Na
Sodium is also present in group1 since it has similar properties to that of Na. It has an electron configuration of 1s2, 2s2, 2p6,3s1.The two electrons fill the 1stsub shell, 8 electrons fill the 2nd and 1 electron fill the outermost shell due to octet rule. Due to the presence of single electron on the outermost shell, Na is placed on the Group 1 with Li.

3. Calcium: Ca
Calcium is places in group 2. It is called an alkaline earth metal. Due to the octet rule it has an electron configuration of 1s2, 2s2,2p6, 3s2, 3p6 , 4s2. Because of this rule two electrons are placed on the outermost shell therefore calcium is placed in group 2.

4. Chlorine: Cl Chlorine has an electron configuration of 1s2, 2s2, 2p6, 3s2, 3p5. To satisfy the octet rule the last 7 electrons are placed on its outermost shell due to which chlorine is placed in group 7.

5. Neon: Ne
Neon is present in group 8 which is classified as noble gas. It has an electron configuration of 1s2, 2s2, 2p6, which allows having 8 electrons in their outermost shell. This results it to have complete outer shell and not react with different elements from other groups.


The atomic structure of chlorine has atomic number of 17 numbers and mass number of 35.5. It has 17 electrons and protons whereas 18 numbers of neutrons. Its electron configuration is 1s2, 2s2, 2p6, 3s2, 3p5. The 1st sub shell is filled with 2 electrons and the last sub shell is filled with 8 electrons. It is also classified as a halogen.

2. Sodium
Sodium has 11 atomic numbers and mass numbers of 23.There are 11 protons and electrons and 12 neutrons in an atom of sodium. The electron configuration is 1s2, 2s2, 2p6, 3s1.The two electrons fill the 1st sub shell whereas eight electrons fill the 2nd sub shell and one electron fills the outermost shell.

Force of attraction between oppositely charged ions.
Sharing of a pair of electrons between two atoms.
Force of attraction between delocalized electrons and the positive centers.
Found between metal and non metal.
Found in non metals.
Only found in metallic elements.
Electron is either gained or lost.
Pair of electrons shared.
Neither gainer nor lost.
Bonding is strong.
Bonding is weak.
Bonding is strong.

1. Relative molecular mass-
Relative molecular mass of a compound is found by adding together the Ar values of each atom in the formula of one molecule. Formula = Ref:

2. Mole-
1 mole is the amount of substance that contains as many particles as there are atoms in exactly 12g of carbon-12. Formula =

3. Molarity-
The number of moles per cubic decimeter of a solution is called its molarity (M). Formula=


AS AQA Chemistry: J. Atkinson, C. Hibbert

P5: Difference between eukaryotic and prokaryotic cells.

They have true nucleus surrounded by a nuclear envelope.
They do not have true nucleus.
Contains endoplasmic reticulum.
Does not contain