TOPIC 5: ATOMIC STRUCTURE The Atom We learned early that matter is made up of small, indivisible particles. Everything around us is made of extremely small particles. These particles are either molecules or atoms. An atom is the smallest indivisible particle of an element that takes part in a chemical change. Atoms are the building blocks of matter. All solids, liquids and gases are made of atoms fitted in different ways. The present day chemistry is built on the foundations of the Atomic Theory. The idea that elements are made up of atoms is called the Atomic Theory. An English…
Author: Msomi Bora
TOPIC 4: FUELS AND ENERGY A fuel is a substance that can be combusted or burnt to release energy as a byproduct. The energy can be in the form of heat, light, electricity, sound etc. This energy can be harnessed to power machines or used for other purposes such as heating or lighting. Combustion is the burning of fuel with energy released as a byproduct. Fuel is a very important substance for the existence of a modern man. Examples of fuels include petroleum products (petrol, diesel, fuel oil, kerosene, spirits, etc), natural gas, coal, wood, charcoal, producer gas, water gas, etc.…
TOPIC 3: WATER Occurrence and Nature of Water The Occurrence and Nature of Water Describe the occurrence and nature of water Water is the most abundant liquid in nature. It is a compound of hydrogen and oxygen. It occurs on land as seas, oceans, rivers, springs, wells, etc. It also occurs in the atmosphere as rain, water vapour, clouds, etc. Water is the essential constituent of animal and plant life. Without water, no life could exist on earth. All living things need water to survive. About 60% of the human body by mass is made of water. A human being…
TOPIC 2: HYDROGEN Hydrogen is the lightest of all the elements. There is very little hydrogen in the earth’s atmosphere. Hydrogen is so light that its molecules are not held by the earth’s gravity and they diffuse into space. Overall, it is the most common element in the universe. It is probable that is forms about 90% of the total mass of the universe. It is believed that the sun composes almost of hydrogen and helium. Hydrogen occurs naturally in air as hydrogen gas. It also occurs in combined state in water, acids, petroleum, and natural gas and in almost…
TOPIC 1: OXYGEN Oxygen exists in air to an extent of 21% by volume (or 23% by weight). It is the most abundant element on earth, accounting for ½ the total mass of the earth’s crust. Oxygen is mainly found in combined states as oxides, hydroxides, silicates, sulphates, carbonates, water, etc. Its ease of combination with other elements to form compounds shows that oxygen is a very reactive element. Preparation and Properties of Oxygen Oxygen can be prepared in the laboratory from either hydrogen peroxide solution or potassium chlorate salt. A Sample of Oxygen Gas in the Laboratory Prepare a…
CHEMISTRY NOTES FOR FORM ONE We have: Notes 1 and Notes 2 Notes 1 To view the Notes, click the following links below: TOPIC 1 – INTRODUCTION TO CHEMISTRYTOPIC 2 – LABORATORY TECHNIQUES AND SAFETYTOPIC 3 – HEAT SOURCES AND FLAMESTOPIC 4 – THE SCIENTIFIC PROCEDURETOPIC 5 – MATTERTOPIC 6 – AIR COMBUSTION, RUSTING AND FIRE FIGHTING Notes 2 To view the Notes, click the following links below: 1. INTRODUCTION TO CHEMISTRY 2. LABORATORY TECHNIQUES AND SAFETY 3. HEAT SOURCES AND FLAMES 4. SCIENTIFIC METHOD 5. MATTER…
TOPIC 6: AIR COMBUSTION, RUSTING AND FIRE FIGHTING Composition of air Air is a mixture of different gases. The gases that make up the air include nitrogen, oxygen, carbon dioxide, noble gases (argon, helium, neon, krypton and xenon) and a little water vapour. Air may also contain traces of impurities such as carbon monoxide (CO), sulphur dioxide (SO2), hydrogen sulphide (H2S) and other gases. The presence of these gases in air results in air pollution. Table bellow shows the composition of air by volume. The proportion of water vapour and impurities in air is very variable. The Gases Present in…
TOPIC 5: MATTER Concept of matter Concept of Matter Explain concept of matter Matter is anything that has mass and occupies space. Therefore, anything around us provided it has mass and can occupy the space, is termed as matter. There are many kinds of matter. Can you mention some? The word matter is used to cover all the substances and materials from which the earth and universe is composed of. These include all materials around us such as water, soil, plants, animals, air, clothes, etc. Any particular kind of matter is called a substance. Substances include elements and compounds. An…
TOPIC 4: THE SCIENTIFIC PROCEDURE Significance of scientific procedure The Concept of Scientific Procedure Explain the concept of scientific procedure The scientific method (procedure) is a process that scientists use to ask questions and conduct investigations to find answers to these problems. It is a logical approach to problem solving by observing and collecting data, formulating hypotheses, testing hypotheses, and formulating theories that are supported by data. The scientific method provides a standardized way for scientists to conduct their work. However, many scientists work according to other methods as well. The Importance of the Scientific Procedure Explain the importance of…
TOPIC 3: HEAT SOURCES AND FLAMES Heat sources Most chemical reactions require heat to proceed. It is therefore important to have sources of heat in a laboratory for heating various reacting substances. Sources of heat in a chemistry laboratory may include Bunsen burner, candle, spirit burner, kerosene burner (stove), tin lamp (kibatari) and charcoal burner. These are burners commonly used in most school laboratories. Different Heat Sources which can be Used in a Chemistry Laboratory Name different heat sources which can be used in a chemistry laboratory The Bunsen burner is the best of all burners because it is convenient…
