[co(h2o)6]2+(aq) + 4cl-(aq) ⇌ [cocl4]2-(aq) + 6h2o(l)
concentrations at 25 degrees c
h+ 9.84368e-8
oh- 9.84368e-8
co (h2o)6^2 0.966539
cl- 1.86616
cocl4^2- 0.0334612
concentrations at 65 degree c
h+ 3.73844e-7
oh- 3.73844e-7
co (h2o)6^2 0.765375
cl- 1.06150
cocl4^2- 0.234625
a. write a k expression for this reaction (note that that liquid water shouldn’t be included in the k expression).
b. use the k expression and equilibrium concentrations on the left to determine the k value at 25 deg c. show all work for full credits.
c. what is the equilibrium constant k’ 65 degrees c?
d. compare the k’ constants; are the value difference agree or against with endo or exothermic determination?

For A: The expression for is given below.

For B: The value of at 25°C is 0.0185512

For C: The value of at 65°C is 0.2887886

For D: The reaction is endothermic in nature.

Explanation:

Equilibrium constant is defined as the ratio of concentration of products to the concentration of reactants each raised to the power their stoichiometric ratios. It is expressed as

For the given chemical reaction:

The expression of for above equation without the concentration of liquid water is:

     ......(1)

The expression is written above.

We are given:

Putting values in equation 1, we get:

Hence, the value of at 25°C is 0.0185512

We are given:

Putting values in equation 1, we get:

Hence, the value of at 65°C is 0.2887886

For Endothermic reactions, , which is positive

For Exothermic reactions, , which is negative

To calculate of the reaction, we use Van't Hoff's equation, which is:

where,

= equilibrium constant at 65°C = 0.2887886

= equilibrium constant at 25°C = 0.0185512

= Enthalpy change of the reaction = ?

R = Gas constant = 8.314 J/mol K

= initial temperature =

= final temperature =

Putting values in above equation, we get:

As, the calculated value of . Thus, the reaction is endothermic in nature.

law of conservation of matter

in 1783 cavendish was working with his hydrogen gas and found that when he burned it and condensed the vapor it was water. this was very significant since it disproved the greek theory of elements completely since water was not a simple substance but the product of two gases. it was lavoisier who hearing of the experiment gave cavendish's gas the name hydrogen ("water-producer") and added that hydrogen burned by combining with oxygen and that water was a hydrogen-oxygen combination.

explanation: