$A$ gas has a density of $2.68 \ g/L$ at $STP$. Identify the gas.

$K_2CS_3$ is called potassium ...... .

$50 \ mL$ of $10 \ N \ H_2SO_4$,$25 \ mL$ of $12 \ N \ HCl$,and $40 \ mL$ of $5 \ N \ HNO_3$ were mixed together,and the volume of the mixture was made $1000 \ mL$ by adding water. The normality of the resultant solution will be.....$N$.

Iron sulphide is heated in air to form $A$, an oxide of sulphur. $A$ is dissolved in water to give an acid. The basicity of this acid is:

When iron sulfide is heated in air,a sulfur oxide $A$ is obtained. When $A$ is dissolved in water,it produces an acid. What is the basicity of this acid?

Who is called the father of chemistry?