Basic & Alkaline Substances — Homi Bhabha Class 6 Chemistry MCQs with Solutions
Free Homi Bhabha Class 6 Chemistry Basic & Alkaline Substances MCQs with step-by-step solutions (10 questions). Part of Acids, Bases and Neutralization. Practise online on Prepizo — no login needed.
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Questions with solutions
Q1 — Basic & Alkaline Substances · easy · theory
Bases usually have a ___ taste.
A. Sour
B. Salty
C. Bitter ✓ Correct
D. Sweet
Solution: Bases such as soap taste bitter. (We should never taste chemicals to check this.)
Q2 — Basic & Alkaline Substances · easy · theory
To the touch, bases usually feel:
A. Grainy
B. Rough
C. Soapy / slippery ✓ Correct
D. Sticky
Solution: Bases like soap solution feel slippery or soapy on the skin.
Q3 — Basic & Alkaline Substances · easy · theory
Which of these is a base?
A. Vinegar
B. Baking soda ✓ Correct
C. Lemon juice
D. Curd
Solution: Baking soda is basic, while lemon juice, vinegar and curd are all acidic.
Q4 — Basic & Alkaline Substances · easy · theory
When red litmus paper is dipped in soap solution, it turns:
A. Blue ✓ Correct
B. Yellow
C. Red
D. Colourless
Solution: Soap solution is basic, and bases turn red litmus blue.
Q5 — Basic & Alkaline Substances · medium · theory
A base that dissolves in water is given a special name. It is called a/an:
A. Salt
B. Alkali ✓ Correct
C. Indicator
D. Acid
Solution: Bases that dissolve well in water are called alkalis, for example sodium hydroxide.
Q6 — Basic & Alkaline Substances · medium · theory
Lime water, used to test a gas in the lab, is itself:
A. Sour
B. Neutral
C. Basic ✓ Correct
D. Acidic
Solution: Lime water is a base, so it turns red litmus blue.
Q7 — Basic & Alkaline Substances · medium · theory
"Milk of magnesia", taken to relieve stomach acidity, is:
A. A salt
B. An acid
C. A base ✓ Correct
D. A sugar
Solution: Milk of magnesia is a mild base that neutralises the extra acid in the stomach.
Q8 — Basic & Alkaline Substances · medium · theory
Many window and floor cleaners contain ammonia. Ammonia is:
A. Basic ✓ Correct
B. Neutral
C. Acidic
D. An indicator
Solution: Ammonia solution is a base, which is why it feels soapy and cleans grease.
Q9 — Basic & Alkaline Substances · hard · theory
Which statement about alkalis is correct?
A. Alkalis are acids that dissolve in water
B. All alkalis are bases, but not all bases are alkalis ✓ Correct
C. Alkalis turn blue litmus red
D. All bases are alkalis
Solution: An alkali is simply a base that dissolves in water, so every alkali is a base but some bases do not dissolve.
Q10 — Basic & Alkaline Substances · hard · theory
A piece of turmeric paper turns red when a liquid is put on it. The liquid is most likely:
A. An acid, like lemon juice
B. A base, like soap solution ✓ Correct
C. Plain sugar water
D. Common salt water
Solution: Turmeric turns red only with a base, so the liquid must be basic.