Fill in the blanks in the following sentences:
(a). Acids have a ______taste and they turn_____litmus to _____
(b). Substances do not show their acidic properties without_____
(c). Acids produce______ions on dissolving in water.
(d). Those substances whose smell (or odour) changes in acidic or basic solution are called _______indicators.
(e). Onion and vanilla extract are_____indicators.

Explanation

(a). Sour, blue, red
(b) water
(c) hydrogen
(d) olfactory
(e) olfactory