Track quiz
Show on a big screenEleven quick questions. Use the table if you get stuck.
| Lesson | The rule |
|---|---|
| Three groups | Never taste an unknown substance. Test it with litmus paper. |
| Acids in food | Foods that taste sour tend to contain an acid. Acids turn blue litmus red. |
| Bases | A base turns red litmus blue. A bitter taste alone does not make a base. |
| Turmeric and rose | Turmeric turns red in a base only. Red rose is red in an acid and green in a base. |
| Neutral | Blue and red litmus both unchanged means neutral. Turmeric cannot tell acidic from neutral. |
| Neutralisation | An acid and a base cancel each other. They make salt and water, and give out heat. |
| Plant indicators | Every indicator has its own colours. Red shows an acid with rose extract but a base with turmeric. |
| Smell indicators | An olfactory indicator changes its smell. Onion smell stays in an acid and fades in a base. |
| Soil and waste | Lime treats acidic soil. Acidic waste is neutralised before release. |
A bottle has no label. How do you find its group?
A liquid turns blue litmus red. Which group is it in?
A liquid turns red litmus blue. Which group is it in?
Which food has lactic acid?
Bitter gourd tastes bitter. What does that show?
Turmeric paper stays yellow in a liquid. Which group is ruled out?
Red rose extract turns green in a liquid. What is the liquid?
Lemon water is made exactly neutral. You add more baking soda water. What happens?
Red rose extract shows red in liquid P. Turmeric paper turns red in liquid Q. Which liquid is basic?
A drop of a liquid goes on an onion strip. The onion smell fades. What does this point to?
A field has basic soil. Why is lime a poor choice?
Your NCERT book calls this chapter Exploring Substances: Acidic, Basic, and Neutral. Read it now. You have already read strips and added drops.
Next: Electricity: Circuits and their Components.
Reveal every answer to finish this lesson.