If a few drops of a concentrated acid accidentally spills over the hand of a student, what should be done

(d) starch,is the correct option.

Numbers of defective pens = 12 Numbers of good pens = 132 Total numbers of pen = 132 + 12 = 144 pens Favourable number of events = 132 Probability of getting a good...

pure water is a bad conductor of electricity. By adding a few drops of sulphuric acid, it becomes a good conductor of electricity

(i) Presence of mind, critical thinking, and dignity of individual. (ii) Pouring dilute sodium hydroxide on the burning hand and keeping in water for 10 minutes can also be done. (iii) 2NaHCO3 +...

The correct answer is (D) only Z

(B) bubbles of a colourless and odourless gas

No reaction with distilled water. Chemical reaction occurs with solution of NaHCO3 Two Observations: (i) Evolution of a colourless, odourless gas. (ii) The gas is evolved with brisk effervescence

When excess of HCl is added, the colour of the final mixture will be colourless because the pink colour of sodium hydroxide is neutralised with the acid.

(i) Acetic acid will remain colourless in phenolphthalein. 22.  (ii) Acetic acid will dissolve in distilled water forming a clear solution.  (iii) Universal indicator gives orange colour with acetic acid.  (iv) Sodium hydrogencarbonate...

Yes. A few drops of sour things like lemon is enough to make out the taste.