Calculate the value of Key in the following reaction if the equilibrium concentrations are [H2S] -0.25 M, (H2) - 0.88 M, [S2] -0.44M.
2 H2Sig) = 2 H2(g) + S218)

The value of the equilibrium constant Kc is 5.45

Explanation:

The "Law of Mass Action" states:

"For a reversible reaction in chemical equilibrium at a given temperature, it is true that the product of the concentrations of the products raised to the stoichiometric coefficients divided by the product of the concentrations of the reactants raised to their stoichiometric coefficients is a constant."

This constant was called the equilibrium constant. For a reaction:

aA + bB ⇄ cC + dD

the equilibrium constant Kc is:

In this case, the balanced reaction is:

2 H₂S → 2 H₂ + S₂

So, the equilibrium constant Kc is:

The equilibrium concentrations are

Replacing in the definition of equilibrium constant:

Solving:

Kc= 5.45

The value of the equilibrium constant Kc is 5.45

a mercury barometer is a device that uses the physical properties of mercury in a tube to measure barometric pressure. mercury barometers are used for : -

1. measurement of atmospheric pressure  

2. determining the altitude of a place

3. weather forecasting

4. calibration and checking of aneroid barometers

5. application in fluid mechanics

6. measurement of pressure in aircrafts

7. surface weather analysis

8. preparation of barographs

9. usage in physical sciences like physics, astronomy & chemistry

10. preparation of aircraft altimeters

characteristics of mercury barometer : -

1.used to define and measure atmospheric pressure.

2.on the average at sea level the column of mercury rises to a height of about 760 mm.

3.this quantity is equal to 1 atmosphere.

4.it is also known as standard atmospheric pressure.

5.a barometer in which the weight of a column of mercury in a glass tube with a sealed top is balanced against that of the atmosphere pressing on an exposed cistern of mercury at the base of the mercury column, the height of the column varying with atmospheric pressure.

when [oh-] is 10-5  m, and [h3o+] is 10-9  m, the poh is 5 and ph is 9. again in both cases the sum of ph and poh is 14. however, the hydrogen ion concentration is not always going to be equal to exactly 1 x 10 raised to a negative number. for example, we skipped over the value of 2.0 x 10-7.