Introduction to chemical reactions
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- Write word and chemical equations to describe basic chemical reactions.
Some hydrochloric acid (HCl) was added to a beaker containing sodium hydroxide (NaOH). A reaction occurred and produced sodium chloride (NaCl) and water (HO).
- Recognise evidence of a chemical change or reaction.
Read the notes from each lab experiment below and highlight which part of the experiment notes shows evidence that a chemical reaction is happening:
Experiment 1: Hexene was added to bromine water in a beaker and stirred thoroughly. Afterward, the brown color disappeared and the mixture became colorless.
Experiment 2: Using a delivery tube and gas syringe, carbon dioxide was bubbled through a solution containing lime water. Over a short time, the lime water became cloudy.
Experiment 3: Sodium hydroxide and sulfuric acid were added to a test tube which was shaken thoroughly. The test tube began to feel warm to the touch.
Experiment 4: Bubbling and fizzing occurred when a strip of magnesium metal was dropped in a solution of hydrochloric acid.
Experiment 5: Iron sulfide powder was added to a solution of hydrochloric acid and a bad smell of rotten eggs was noticed.