We should not touch and taste acids and bases in laboratory. Why?
Edible soda is used for cooking rice in hotels. Why?
Sound wave cannot propagate through vaccum. Why?

the Acids, even the weakest acids can burn you, even scar you. The most common base (besides the weak sodium bicarbonate solution) is Sodium Hydroxide, and it will burn soft tissues, like the mouth, lips and tongue. One more thing, in a teaching laboratory, what is on the label may not be what is in the bottle, and even if it is, you cannot know If there are any contaminants of who knows what!

IN the LAB - Never lick the spoon!

Edible soda, or NaHCO3 is a base that when cooked with rice softens it, but becomes Na+, Water and carbon dioxide; and is useful for many things requiring a VERY weak Hydrolyzing base.

Sound is the results of vibration in the air, the waves. In a vacuum there is no air, And therefore, no sound!

Never taste the Chemicals!

the correct answer: the index of refraction of the second medium is lower i tried this persons answer and it was wrong this person is lying