GATE CE 2026 Set 2 — Question 63

NAT+2 / -0HardpH, Turbidity, Hardness & AlkalinityWater QualityEnvironmental EngineeringChlorinationDrinking Water Treatment

Environmental Engineering → Drinking Water Treatment → Chlorination

Last updated 5 September 2026

Question

Cl^-

Anions	$Cl^-$	$SO_4^{2-}$	$HCO_3^-$	$CO_3^{2-}$
Concentration (mM)	1.5	0.5	1.0	0.01

Cations	$Na^+$	$Ca^{2+}$	$Mg^{2+}$	$K^+$
Concentration (mM)	2	0.5	0.25	0.02

K_2 = \frac{[H^+][CO_3^{2-}]}{[HCO_3^-]} \Rightarrow 10^{-10.3} = \frac{[H^+] \times 0.01 \text{ mM}}{1.0 \text{ mM}}

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K_2 = \frac{[H^+][CO_3^{2-}]}{[HCO_3^-]} \Rightarrow 10^{-10.3} = \frac{[H^+] \times 0.01 \text{ mM}}{1.0 \text{ mM}}

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