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Question
The metal M reacts vigorously with water to form a solution S and a gas G. The solution S turns red litmus to blue whereas gas G, which is lighter than air, burns with a pop sound. Metal M has a low melting point and it is used as a coolant in nuclear reactors.
- What is metal M?
- What is solution S? Is it acidic or alkaline?
- What is gas G?
- Write a balanced chemical equation for the reaction which takes place when metal M reacts with water.
- Is this reaction exothermic or endothermic?
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Solution
- Metal M is sodium (Na), which is used as a coolant in nuclear reactors.
- Solution S is a sodium hydroxide solution (NaOH). It is alkaline; it turns red litmus to blue.
- Gas G is hydrogen gas, which is lighter than air.
- \[\ce{2Na_{(s)} + 2H2O_{(l)} -> 2NaOH_{(aq)} + H2_{(g)} + HEAT}\]
- This reaction is exothermic because it releases excessive heat.
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