Class 7 chemistry physical and chemical change

Tick (✔) The correct choice amongest the following 1. Sublimation of iodine is a : (a) Chemical change (b) Physical change (c) Periodic change (d) Irreversible change 1 Mark(s) 2. When magnesium ribbon is burnt, heat and light are produced. It is an example of : (a) Chemical change (b) Physical and irreversible change (c) Chemical and exothermic change (d) Chemical and endothermic change 1 Mark(s) 3. Powdering of sugar is : (a) Chemical and irreversible change (b) Physical change (c) Reversible change (d) Irreversible change 1 Mark(s) 4. Making ice from water is an example of : (a) Man-made change (b) Chemical change (c) Sublimation (d) Undesirable change 1 Mark(s) 5. Melting of butter is not a : (a) Fast change (b) Desirable change (c) Reversible change (d) Permanent change 1 Mark(s)

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Write True False for each statement, Rewrite the false statements 1. In an exothermic reaction, heat is given out. 1 Mark(s) 2. In a chemical reaction no new substance is formed. 1 Mark(s) 3. Reaction of zinc pieces with hydrochloric acid is an exothermic reaction. 1 Mark(s) 4. Glowing of an electric bulb is a physical change. 1 Mark(s) 5. Breaking of a glass tumbler is a reversible change. 1 Mark(s) 6. Burning of wood is a chemical change. 1 Mark(s)

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Select the Odd and Out Giving reason 1. Burning of wood, rusting of iron, souring of milk, freezing of water. 1 Mark(s) 2. Freezing of water, magnetising an iron nail, breaking of chalk stick. 1 Mark(s) 3. Rusting, burning, combustion, melting. 1 Mark(s)

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