1) What is a change? a) Staying the same b) Transformation in state, form, or shape c) Only change in color d) Only change in size 2) I can change my shape without changing my soul, I melt when heated but stay the same whole. What am I? a) Candle wax b) Ice c) Magnesium d) Rust 3) Which of these is a Physical change? a) Rusting of Iron b) Melting Ice c) Burning paper d) cooking an egg 4) I make iron turn orange-brown over time, You can’t reverse me, though I seem fine. What am I? a) Rust b) Ice c) Salt d) Water 5) I shine bright, I disappear fast, When I meet oxygen, my light will last. What am I? a) Burning magnesium b) Ice c) Candle wax d) Rust 6) Which of these is a chemical change? a) Cutting paper b) Dissolving sugar in water c) burning magnesium d) melting butter 7) Chemical changes are usually a) Reversible b) Irreversible c) Only in liquids d) Only in solids 8) Physical changes are usually a) Reversible b) Irreversible c) Always chemical d) Dangerous 9) which of these changes is reversible? a) Rusting of iron b) Freezing water c) Burning wood d) Cooking rice 10) Which of these changes is irreversible? a) Melting ice b) Dissolving salt c) Burning magnesium d) Freezing water 11) Rusting of Iron is a... a) Physical change b) Chemical change c) Reversible change d) None 12) Word equation for rusting of iron: a) Iron + Oxygen → Iron oxide b) Iron + Oxygen + Water → Hydrated iron(III) oxide c) Iron + Carbon → Iron carbide d) Iron → Rust 13) You can cut me, break me, or shape me, I stay the same, chemically. What am I? a) Paper b) Candle wax c) Ice d) All of the above 14) Burning magnesium ribbon is a: a) Physical change b) Chemical change c) Reversible change d) Melting 15) Chemical equation for rusting of iron: a) Fe + O₂ → FeO b) 2Fe + O₂ + H₂O → Fe₂O₃ c) 4Fe + 3O₂ + 6H₂O → 4Fe(OH)₃ d) Fe + H₂O → Fe(OH)₂ 16) Why is melting of a candle a physical change? a) It produces new substances b) Composition remains the same, only state changes c) It releases heat d) It burns 17) Melting of a candle is a: a) Irreversible b) Physical change c) Chemical change d) Both physical & chemical 18) Chemical equation for burning magnesium ribbon: a) Mg + O₂ → MgO b) 2Mg + O₂ → 2MgO c) Mg + H₂O → Mg(OH)₂ d) Mg → MgO 19) I’m solid now, but heat makes me flow, I’m used to light up a room or show. What am I? a) Ice b) Candle wax c) Magnesium d) Rust 20) Word equation for burning magnesium ribbon: a) Magnesium + Oxygen → Magnesium oxide b) Magnesium → Magnesium fire c) Magnesium + Water → Magnesium hydroxide d) Magnesium + Hydrogen → Magnesium hydride

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