When dilute $H_2SO_4$ is added to an aqueous solution of potassium chromate,the yellow color of the solution changes to orange. This indicates that .....

The increasing order of $pH$ of $0.1 \ M$ solution of the following compounds is:

$A$ soft drink was bottled with a partial pressure of $CO_2$ of $3 \ bar$ over the liquid at room temperature. The partial pressure of $CO_2$ over the solution approaches a value of $30 \ bar$ when $44 \ g$ of $CO_2$ is dissolved in $1 \ kg$ of water at room temperature. The approximate $pH$ of the soft drink is............... $\times 10^{-1}$ (First dissociation constant of $H_2CO_3 = 4.0 \times 10^{-7}$; $\log 2 = 0.3$; density of the soft drink $= 1 \ g \ mL^{-1}$)

Arrange the following resultant mixtures in increasing order of their pH values:
$A$. $10 \text{ mL } 0.2 \text{ M } Ca(OH)_2 + 25 \text{ mL } 0.1 \text{ M } HCl$
$B$. $10 \text{ mL } 0.01 \text{ M } H_2SO_4 + 10 \text{ mL } 0.01 \text{ M } Ca(OH)_2$
$C$. $10 \text{ mL } 0.1 \text{ M } H_2SO_4 + 10 \text{ mL } 0.1 \text{ M } KOH$
Choose the correct answer from the options given below:

$20 \ mL$,$0.1 \ M \ HA$ $[(K_b)_{A^-} = 10^{-10}]$ is titrated against $0.2 \ M \ NaOH$. Select the correct statement [Given : $\log 2 = 0.3, \log 3 = 0.48$ ]

$A$ sample of $Na_2CO_3 \cdot H_2O$ weighing $0.62 \ g$ is added to $100 \ mL$ of $0.1 \ N \ (NH_4)_2SO_4$ solution. What will be the nature of the resulting solution?