The student placed 10 ml of pbcl2 (saturated solution) in the test tube and added a pinch of nacl. a white precipitate of pbcl2 formed. how will this affect the concentration of pb+2?

Concentration of decreases

Explanation:

In a saturated solution of , the following solubility equilibrium exist-

Now, NaCl contains common ion . Therefore, concentration of increases in solution.

But, at a particular temperature, equilibrium constant remain constant. Therefore to keep equilibrium constant same will reacts with excess to decrease concentration of .

Therefore concentration of decreases.

Note: Equilibrium constant for the above equilibrium=

the equation that correctly represent the reaction for formation of ammonia is

n2+ 3h2 → 2nh3 (answer d)

1 mole of nitrogen gas (n2) react with 3 moles of hydrogen gas (h2) to form 2 moles of ammonia ( nh3). this is in a process known as haber process were iron is used as a catalyst and reaction take place that a higher temperature and pressure. the process is exothermic hence energy is released.