Question

Which one of the following reacts with concentrated ${{H}_{2}}S{{O}_{4}}$?
A. $Au$
B. $Ag$
C. $Pt$
D. $All$

Answer 1

${{H}_{2}}S{{O}_{4}}$ is known by the name sulphuric or sulfuric acid and also known as oil of vitriol. It is generally a mineral acid made up with the elements sulfur, oxygen and hydrogen which is represented by the formula given i.e. ${{H}_{2}}S{{O}_{4}}$.

Complete Solution :
${{H}_{2}}S{{O}_{4}}$ is generally colorless, odorless and viscous liquid which is soluble in water. ${{H}_{2}}S{{O}_{4}}$synthesized by those reactions which are highly exothermic in nature i.e. large amounts of heat produced in such types of reactions. It is one of the strongest acids so the corrosiveness of ${{H}_{2}}S{{O}_{4}}$ towards other materials can be described due to its strong acidic property. Sulfuric acid reacts with many metals through single displacement reactions and produces hydrogen gas or water and salts during the reaction and it attacks only reactive metals i.e. only those metals which are present above copper in the reactivity series. But metal given in the questions are all least reactive but $Ag$is most reactive out of these three so we can say that ${{H}_{2}}S{{O}_{4}}$ reacts with $Ag$ and reaction can be shown as:
$2{{H}_{2}}S{{O}_{4}}+2Ag\to AgS{{O}_{4}}+2{{H}_{2}}O$
So, the correct answer is “Option B”.

Note: Sulfuric acid is also known to be hygroscopic in nature which defines that it readily absorbs water vapor from the air. Within the contact sulfuric acid can cause severe chemical burns and even secondary thermal burns due to dehydration therefore it is kept in the category of dangerous acids even at lower concentrations.