Number 18 is correct, number 19 is the particles speed up and the substance expands, and number 20 is decrease in volume
Answer:- d) 42 kJ of heat is released and the reaction is exothermic.
Solution:- Heat of reaction is the summation of heats of products - reactants.
![\Delta H_r_x_n=\sum [products-reactants]](https://tex.z-dn.net/?f=%5CDelta%20H_r_x_n%3D%5Csum%20%5Bproducts-reactants%5D)
From given information, the energy contained by products is 352 kJ and the energy contained by reactants is 394 kJ. Let's plug in the values in the formula:
= [352 kJ - 394 kJ]
= -42 kJ
Heat of reaction is -42 kJ. The negative sign indicates the heat is released means the reaction is exothermic.
So, the correct option is the last one, 42 kJ of heat is released and the reaction is exothermic.
Answer:
The temperature at which the reaction changes from non-spontaneous to spontaneous is 588.735 K
Explanation:
The spontaneity of a reaction is determined by the change in Gibbs Free Energy,
.

If
is greater than zero, then a reaction is feasible.
If
is less than zero, then a reaction is not feasible.
To determine the temperature at which the reaction changes from non-spontaneous to spontaneous, we should equate the
to zero.
We take
as the limiting condition.

Therefore, the temperature is: 588.735K
99.98%=0.9998
0.01%=0.0001
=(1)(0.9998)+2(0.0001)+3(0.0001)
=1.0003
<span>A solute and a solvent are mixed together. In order to say that the substances form a homogeneous solution, it should be that the solute dissolve completely in the solvent that is you would not be able to see solute particles separate from the solvent. Hope this answers the question. Have a nice day.</span>