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The concentration of fluoride, lead, nitrate, and iron in a water sample from an underground lake was found to be 1000 ppb, 40 ppb, 100 ppm, and 0.2 ppm, respectively. This water is unsuitable for drinking due to the high concentration of

Answer:

Explanation:

 This water is unsuitable for drinking due to the high concentration of nitrate. In drinking water. the maximum permissible concentration of

$lead \simeq 50 ppb$

$nitrate\simeq 50ppb$

$iron \simeq 0.2ppm$

$fluroide\simeq 1 ppm$

Which one of the following ores is best concentrated by froth floatation method

Answer:

Explanation:

Sulphide ores are concentrated by the froth floatation method e.g. Galena (PbS).

Which one of the following statements about water is false?

Answer:

Explanation:

There is extensive intermolecular H-bonding in the condensed phase.

The equilibrium constant at 298 K for a reaction $A+B \rightleftharpoons C+D$ is 100. If the initial  concentrations of all the four species were I M each, then the equilibrium concentration of D(in Mol L-1) will be 

Answer:

Explanation:

                      $ A + B \rightleftharpoons  C  +  D $

initially at t=0,  1      1                             1      1

At equilibrium  1+x   1+x                          1-x    1-x

$K_{eq}=\frac{[C][D]}{[A][B]}$

$=\frac{(1+x)(1+x)}{(1-x)(1-x)}=\frac{(1+x)^2}{(1-x)^2}$

$100= \left(\frac{1+x}{1-x}\right)^2$

$10=\frac{1+x}{1-x}$

$10-10x=1+x$

$9=11x$

$x=\frac{9}{11}=0.818$

D=1+x=1+0.818=1.818

The absolute configuration of

Answer:

Explanation:

For C-2, the order of priority of substituents is 

OH>CH(Cl)(CH₃)>COOH

For C-3 , order of priority of substituents is 

Cl>CH(OH)COOH>CH₃

Hence,according to CIP rules ,

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