CORONA-19 is a respiratory disease as it mainly affects the lungs. It is transmitted from an infected person mostly by respiratory droplets released into the air when an infected person sneezes or coughs directly without covering his mouth or nose. ...

We will find fine microscopic sulphur particles precipitating in about 2 and 3 minutes due to the reaction between sulphuric acid sodium thiosulphate.

Out of the given four materials the refractive index of glycerine is highest. So, greatest deviation of incident light ray is observed in case of glycerine.

As MnO₂ reacts with HCl to form salt, water and chlorine gas, it is basic oxide since it reacts with an acid. Moreover, oxides of metal are basic in nature whereas oxides of non-metals are acidic in nature.

Autotrophs take in food from the outside world and convert them into stored forms of energy. This material is taken in the form of carbon dioxide and water which is converted into carbohydrates in the presence of sunlight and chlorophyll.