ROUND-UP 1 Fill in the sentences with a suitable word for each blank space. ...................... chemistry studies molecules containing carbon. Carbon ...................... combine together in a multiplicity of ways. Organic ...................... are all around us and shape our world. ...................... consist of smaller molecules bonded together. Characteristic chemical reactions of molecules are determined by ...................... ...................... of atoms. The two major classes of hydrocarbons are ...................... compounds and aromatic compounds. ...................... is the simplest aromatic compound. In ......................, oxygen-hydrogen molecules are linked to hydrocarbons. 1. 2. 3. 4. 5. 6. 7. 8. ...................... made of ...................... can have many ......................, among which being: Polymers – plastic – disadvantages – non-biodegradable Plastic – polymers – advantages – non-biodegradable Plastic – polymers – disadvantages – biodegradable Polymers – plastic – disadvantages – biodegradable 3. a. b. c. d. ...................... or more sugars make up ...................... carbohydrates, which are divided into ...................... and ...................... Three – complex – oligosaccharides – polysaccharides Two – complex – monosaccharides – polysaccharides Three – simple – monosaccharides – polysaccharides Three – simple – oligosaccharides – disaccharides 4. a. b. c. d. 2 Choose the right option. Polymers are ...................... organic ...................... molecules consisting of ...................... repeating ...................... units. small – molecules – larger – atomic large – molecules – smaller – atomic large – molecules – smaller – molecular small – atomic – larger – molecular 1. a. b. c. d. ...................... soften when ...................... and can be shaped when hot, ...................... harden when ...................... Thermoplastics – shaped – thermosets – heated Thermosets – heated – thermoplastics – shaped Thermosets – heated – thermoplastics – moulded Thermoplastics – heated – thermosets – moulded 2. a. b. c. d. 3 Answer the following questions. Into how many groups are aliphatic compounds divided? What is the difference between an addition polymer and a condensation polymer? Why is synthetic rubber preferable to natural rubber? What is a disadvantage of polymers? What are proteins made up of? How are carbohydrates produced? What are the major roles of lipids? What makes up nucleic acids? 1. 2. 3. 4. 5. 6. 7. 8.