Here are the answers to the questions at the bottom of your worksheet:
1. Explain the pH scale. (What does a pH of 7 mean?)
The pH scale is a way to measure how acidic or basic (alkaline) a substance is. It usually goes from 0 to 14.
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pH less than 7: The substance is an
acid.
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pH greater than 7: The substance is a
base.
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pH of 7: This means the substance is
neutral. It is neither an acid nor a base. Pure water is the most common example of something with a pH of 7.
2. Why is a substance at either end of the pH scale considered dangerous?
Substances at the ends of the scale are very strong and can cause chemical burns or severe damage to skin, eyes, and other tissues.
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Low end (0-2): These are strong acids (like battery acid) that can burn through materials and flesh.
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High end (12-14): These are strong bases (like drain cleaner) that are also highly corrosive and dangerous to touch or swallow.
3. Define the term Salt and explain a neutralization reaction.
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Salt: In chemistry, a salt is a compound formed when an acid reacts with a base. It is made up of positive ions from the base and negative ions from the acid. Table salt (sodium chloride) is just one type; there are many different salts.
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Neutralization Reaction: This happens when an acid and a base mix together. They react to cancel each other out, producing two new things:
salt and
water. The result is usually closer to neutral (pH 7) than the original acid or base was.
Parent Tip: Review the logic above to help your child master the concept of acid base worksheet.
