Recent questions and answers in Principles of Water Chemistry

Which of the following options is/are CORRECTLY listing the species included in Total Kjeldahl Nitrogen (TKN) estimation of an aqueous sample?Ammoniacal - $\text{N}$Nitri...

The analysis of a water sample is shown in the table. The hardness of the water sample is $\_\_\_\_$ $\mathrm{mg} / \mathrm{L}$ as $\mathrm{CaCO}_{3}$.Atomic weight $(\ma...

The following two reactions describe the chemistry of $\text{S(IV)}$ in an aquatic system.Under ideal conditions, the equilibrium constants for reactions $\text{(i)}$ and...

The calibration graph between absorbance and the concentration of chromate $\left(\mathrm{CrO}_{4}{ }^{2-}\right)$ in a water sample is shown in the figure.For an absorba...

​​​​Choose the redox reaction from the following$\mathrm{H}_{2} \mathrm{CO}_{3} \leftrightarrow \mathrm{H}^{+}+\mathrm{HCO}_{3}^{-}$$\mathrm{Hg}^{2+}+2 \mathrm{OH}^{-} \l...

​​​​A researcher added certain amount of $\mathrm{HgCl}_{2}$ to water at $\mathrm{pH} 10$. He calculated the expected concentration of mercury in the water. He asked his ...

​​​​​Correctly label the speciation diagram below:$\mathrm{I}=\mathrm{PO}_{4}{ }^{3-}, \mathrm{II}=\mathrm{HPO}_{4}{ }^{2-}, \mathrm{III}=\mathrm{H}_{2} \mathrm{PO}_{4}{ ...

​​​​​Choose the correct option(s) from the following regarding the solubility in waterWater is a polar molecule because of the asymmetric distribution of charge between t...

Water from a hand pump located near a landfill has $1 \mathrm{mg} / \mathrm{L}$ arsenic (oral carcinogenic potency factor $=1.75(\mathrm{~kg-day}) / \mathrm{mg})$. A pers...

Hardness in water is NOT caused by$\mathrm{Ca}^{2+}$$\mathrm{Si}^{2+}$$\mathrm{Mg}^{2+}$$\mathrm{CO}_{3}^{2-}$

A saturated $\mathrm{CaCO}_{3}$ stock solution is existing at $25^{\circ} \mathrm{C}$. In one experiment $\text{(i)}$ $25 \mathrm{~g}$ $\mathrm{Na}_{2} \mathrm{CO}_{3}$ i...

The ionic strength of a solution containing $0.01 \mathrm{M}$ of $\mathrm{CaCl}_{2}$ and $0.001 \mathrm{M}$ of $\mathrm{Na}_{2} \mathrm{SO}_{4}$ is _________ $\mathrm{M}$...

The $\mathrm{pH}$ of a solution containing $0.1 \mathrm{M}$ of acetic acid and $0.05 \mathrm{M}$ of sodium acetate is __________ $\text{(rounded off to $2$ decimal places...

An industry discharges $2$ million liters per day $\text{(MLD)}$ of wastewater with a temperature of $45^{\circ} \mathrm{C}$ and a $\mathrm{pH}$ of $2$, whereas the neigh...

A person consumes $2.5$ liters of water per day. The water quality test indicated that the supplied water has a $\mathrm{Pb}$ concentration of $0.6 \mathrm{mg} / \mathrm{...

For testing alkalinity for a water sample, first phenolphthalein indicator is added. The water remains colorless. However, when a few drops of methyl orange is added to t...

The solubility of gas A is $16 \mathrm{mg} / \mathrm{L}$ in water and its vapor pressure is $0.042 \mathrm{~atm}$. at $25^{\circ} \mathrm{C}$. In a closed system, the gas...

Chlorine is most effective as a water disinfectant at a $\text{pH}$ of _____________.$6$ $8$$10$$12$

What is the $\text{pH}$ of a water sample having $\mathrm{H}^{+}$ concentration of $10$ $\mathrm{mg} / \mathrm{L}$?The atomic weight of $\mathrm{H}$ is $1 \mathrm{~g} / ...

A $200 \mathrm{~mL}$ sample of water has an initial $\mathrm{pH}=9$. In order to determine alkalinity, the sample was titrated using $0.02 \mathrm{~N} \mathrm{H}_2 \mathr...