Chemistry
⏱ ~3-min readAceMark Guide
What this topic is really about
Sodium chloride is formed by ionic bonding, where a sodium atom transfers its single outer electron to a chlorine atom, creating oppositely charged ions that attract. Covalent bonding is incorrect because it involves sharing electrons between non-metals, rather than transferring them between a metal and a non-metal.
Pure water is neutral, which corresponds to exactly pH 7 on the pH scale because the concentration of hydrogen ions equals hydroxide ions. Distractors like pH 1 and pH 14 represent highly acidic and highly alkaline solutions, respectively, rather than neutral substances.
See the mechanism
Pure water is neutral, which corresponds to exactly pH 7 on the pH scale because the concentration of hydrogen ions equals hydroxide ions. A diagram for this topic isn't available yet — the worked example below walks the same reasoning step by step.
An exam-style question, fully explained
The pH of pure water is:
- Identify what the question tests: The pH of pure water is:.
- Pure water is neutral, which corresponds to exactly pH 7 on the pH scale because the concentration of hydrogen ions equals hydroxide ions.
- Distractors like pH 1 and pH 14 represent highly acidic and highly alkaline solutions, respectively, rather than neutral substances.
Traps the examiner sets
- Covalent bonding is incorrect because it involves sharing electrons between non-metals, rather than transferring them between a metal and a non-metal.
Test your recall
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