Last updated on December 9th, 2023 at 09:07 pm
Que: How is turmeric paper created?
a) By applying turmeric paste to filter paper and drying it
b) By applying vinegar to blotting paper and drying it
c) By applying lemon juice to filter paper and drying it
d) By applying baking soda to blotting paper and drying it
Answer: a) By applying turmeric paste to filter paper and drying it
Que: What happens to the color of turmeric paper when a drop of soap solution is added?
a) It turns red
b) It turns blue
c) It turns yellow
d) It remains unchanged
Answer: b) It turns blue
Que: What is requested from the teacher for further demonstrations?
a) Turmeric powder
b) Soap solution
c) Dilute solutions of various chemicals
d) Blotting paper
Answer: c) Dilute solutions of various chemicals
Que: What is introduced as a new indicator for the demonstration?
a) Turmeric powder
b) Soap solution
c) Phenolphthalein
d) Blotting paper
Answer: c) Phenolphthalein
Que: What is the initial color of the dilute hydrochloric acid in the test tube?
a) Red
b) Blue
c) Yellow
d) Clear/colorless
Answer: d) Clear/colorless
Que: What is added to the acid in the test tube to observe any change in color?
a) Vinegar
b) Turmeric powder
c) Phenolphthalein solution
d) Soap solution
Answer: c) Phenolphthalein solution
Que: What is the result when an acidic solution is mixed with a basic solution in suitable amounts?
a) The solution becomes acidic
b) The solution becomes basic
c) The solution becomes neutral
d) The solution becomes concentrated
Answer: c) The solution becomes neutral
Que: What happens to the temperature of the reaction mixture during neutralization reactions?
a) It decreases
b) It remains unchanged
c) It increases
d) It fluctuates
Answer: c) It increases
Que: What substance is formed during neutralization reactions?
a) Acid
b) Base
c) Salt
d) Water
Answer: c) Salt
Que: What is the general equation for neutralization reactions?
a) Acid + Base → Salt + Water (without heat evolution)
b) Acid + Base → Salt + Water (with heat evolution)
c) Acid + Base → Salt + Oxygen (with heat evolution)
d) Acid + Base → Salt + Carbon dioxide (with heat evolution)
Answer: b) Acid + Base → Salt + Water (with heat evolution)
Que: Which reaction is given as an example of neutralization?
a) HCl + NaOH → NaCl + H2O
b) H2O + NaCl → HCl + NaOH
c) NaOH + NaCl → HCl + H2O
d) NaCl + H2O → HCl + NaOH
Answer: a) HCl + NaOH → NaCl + H2O
Que: What would be the result of adding dilute sulfuric acid to lime water?
a) The reaction mixture becomes acidic
b) The reaction mixture becomes basic
c) The reaction mixture becomes neutral
d) The reaction mixture becomes hot
Answer: d) The reaction mixture becomes hot
Chapter – Class 7 Science Acids, Bases, and Salts
