Alyn G. McFarland & Teresa Quigg
Published in: Hodder Education
Release Year: 2015
ISBN: 978 1471 807671
Pages: 378
Edition: First Edition
File Size: 27 MB
File Type: pdf
Language: English

Description of Chemistry

Protons have a positive charge (relative charge = +1), electrons have a negative charge (relative charge = −1) and neutrons have no charge at all (relative charge = 0). The mass of an atom is centered in the nucleus as the mass of electrons is very much less than the mass of protons and neutrons. The relative mass of a proton is 1; the relative mass of a neutron is 1 but the relative mass of an electron is 1 1840. 
Electrons are arranged in shells at increasing distances from the nucleus. There is a maximum number of electrons that each shell can hold. The shells closest to the nucleus fill first.
● The number of protons in the nucleus of an atom of a particular element is the same as the atomic number for that element.
● In an atom, the number of protons is equal to the number of electrons. This makes atoms electrically neutral (have no charge).
● The number of neutrons is equal to the mass number – the atomic number.
● The mass number and atomic number are often written before the symbol for the element as for example, 23 11Na, where 11 is the atomic number for sodium and 23 is the mass number for this atom of sodium.
● Atoms of the same element with the same number of protons and a different number of neutrons are called isotopes. For example, boron has two isotopes: 10 5B and 11 5B. An atom of 10 5B contains 5 protons,5 electrons, and 5 neutrons; an atom of 11 5B contains 5 protons, 5 electrons, and 6 neutrons.
● The electronic structure of an atom is determined by the number of electrons. The first shell can hold a maximum of 2 electrons, the second shell can hold 8 electrons and the third shell can hold a maximum of 8 electrons.
● For example, an atom of sodium (atomic number 11, mass number 23) has 11 protons in the nucleus; 11 electrons arranged in shells and 12 (= 23 – 11) neutrons in the nucleus. The 11 electrons are arranged 2 in the first shell; 8 in the second shell and 1 in the third shell – this is often written as 2, 8, 1 for the electronic structure or electron configuration.

Content of Chemistry

1 Atomic structure 1
2 Amount of substance 27
3 Bonding 75
4 Energetics 118
5 Kinetics 144
6 Chemical equilibria and Le Chatelier’s principle 154
7 The equilibrium constant, Kc, for homogeneous
systems 167
8 Oxidation, reduction and redox equations 189
9 Periodicity and Group 2 212
10 Halogens 226
11 Introduction to organic chemistry 244
12 Alkanes 264
13 Halogenoalkanes 278
14 Alkenes 296
15 Alcohols 316
16 Organic analysis 334
17 Maths for chemistry 348
Similar Books