Concentrated `H_(2)SO_(4)` can't act as a`//`an

Options

A. reducing agent
B. oxidizing agent
C. dehydrating agent
D. drying agent

Answer

1

Explanation

Since `S` in `H_(2SO_(4)` is present in its highest possible oxidation state `(6+)`, it can't act as a reducing agent .Concentrated `H_(2)SO_(4)` has a great affinity for water ,forming hydrates very rapidly .Much heat is liberated when the acid is mixed with water.Therefore ,dilute sholud always be performed cautiously by pouring the acid slowly into water with constant stirring .If water is added to the concentrated `H_(2)SO_(4)` there is a dange rthat apocket a steam may be produced which might blow the acid out of the vessel.
Because it is very hygroscopic ,the concentrated `H_(2)SO_(4)` is used for drying gases although it must be used for basic substance such as ammonia, nor for reducing agents such as hydrogen sulphide. It is sometimes used as a drying agent in desiccators.
So great is it savidity for water that the concentrated acid particularly when hot, decomposes substances containing `H` and `O` and removes these element as water. For example cane sugar is converted into mass of suger carbon(charring),and formic and oxalic acids are dehydrated to carbon monoxide:
`C_(12)H_(22)O_(11)rarr12C+11H_(2)O`
`HCO_(2)HrarrCO(g)+H_(2)O`
`(COOH)^(2)rarrCO(g)+CO_(2)(g)+H_(2)O`
Similarly ,paper,wood,clothes and starch are readily dehydrates and charred by the hot concentrated acid, its corrosive action on skin is also due to dehydration of skin. Hot concentrated `H_(2)SO_(4)` has quite strong oxidizing properties. Thus when`NaBr` is dissolved in concentrated `H_(2)SO_(4),HBr` is formed but in addition some `Br^(-)` ions are oxidized to`Br^(2)`. `Cu` does not react with acids because it is lower than `H` in the electrochemical series. However, several noble metals including `Cu` dissolve in cone. `H_(2)SO_(4)` due to its oxidizing properties .The oxidizing properties of `SO_(4)^(2-)` convert `Cu` into `Cu^(2+)`.