Manufactured Substances in Industry

Question 3: Traditional ceramics are made from clay such as kaolin.(a) Name two oxide compounds found in kaolin.(b) Give the formula of the ion that produces brown colour in clay.(c) State two uses of traditional ceramics. Answer:(a) Silicon dioxide and aluminium oxide(b) Fe3+ ion(c) Manufacture of ceramics and bricks Question 4:The various unique properties of … Read more

Question 1:The addition of coke (carbon) in the extraction process of iron is to remove oxygen from iron ore. The iron and carbon mixture will form steel. Table 1 shows two types of steel with different percentage of carbon.(a) Cast iron is brittle whereas high-carbon steel is hard and strong. Based on Table 1, calculate … Read more

Question 1:Concrete is an example of composite material that has been used since ancient times.(a) What is the meaning of composite material?(b) Is concrete suitable to be used to build the pillars of buildings? Explain.(c) Explain how concrete may be reinforced.(d) State two uses of reinforced concrete. Answer:(a) Combination of two or more non-homogeneous substances(b) … Read more

Question 1: Fill in the blanks:(a) Ceramic is a non ________ solid element and non ________ compound.(b) Give three examples of substances that make up ceramics.  Answer:(a) metal; organic(b) Carbon, titanium carbide, silicon carbide Question 2:Silicon carbide is an example of advanced ceramic that has a hard structure and diamond-like properties. Can silicon carbide be … Read more

Question 1:Silica is used to make all types of glass.(a) State the type of glass that is made up of only silica. (b) Soda-lime glass contains alkali metal ions. Name the ion. Answer:(a) Fused silica glass (b) Sodium ion Question 2:A sample of borosilicate glass has composition of 80% silica, SiO2, 15% boron oxide, B2O3 … Read more

Question 1:Atoms in pure iron are arranged in an orderly manner and in layers.(a) What is the effect of atom arrangement in pure iron on the ductility and malleability of the metal?(b) Iron alloy can be made by mixing some carbon into molten iron. How does the arrangement of atoms in the iron alloy affect … Read more

Experiment 8.1:Aim: To investigate the comparison between the properties of alloys and pure metals.Problem statement: Is an alloy more resistant to corrosion and harder than a pure metal?Materials: Stainless steel plate, iron plate, distilled water, bronze block and copper blockApparatus: 100 cm3 beaker, 100 cm3 measuring cylinder, sandpaper, steel ball bearing, 1 kg weight, retort … Read more

Composite materials are substances which contain 2 or more materials that combine to produce new substances with different physical properties from the original substances. Some composite materials and their components are: Reinforced Concrete Component: Concrete (cement, sand, stones), steel Ordinary concrete is strong but heavy. Concrete pillars must be big to support the weight. They … Read more

New Uses of Glass and Ceramics Photochromic Glass Photochromic glass is very sensitive to light. It darkens in the presence of bright light and lightens when the amount of sunlight lessens. Conductive Glass Conducting glass is a type of glass which can conduct electricity. It is obtained by coating a thin layer of a conducting … Read more

Ceramics Ceramic is a substance that is made from clay and hardened by heat in a furnace maintained at a high temperature. Clay is composed of aluminosilicate with sand and iron(III) oxide as impurities. Examples of ceramics include Tiles Cement Bricks porcelain The properties of ceramics include the following: The differences between the properties of … Read more