VII . A because it contains Br (l), Cl (g) and I (s)
Answer:
A reaction is spontaneous if ΔG is negative.
Explanation:
- The change in free energy (ΔG) is the difference between the heat released during a process and the heat released for the same process occurring in a reversible manner.
- The sign of ΔG gives an indication for the spontaneity of the reaction:
If ΔG is negative, the reaction is spontaneous.
If ΔG = zero, the reaction is at equilibrium.
If ΔG is positive, the reaction is non-spontaneous.
Explanation:
The given reaction is redox reaction but not combustion reaction.
Redox reaction : It is a chemical reaction in which oxidation and reduction occurs simultaneously.Oxidation is gaining of electrons and reduction is loosing of electrons.
oxidation
reduction
Potassium when reacts with water ,gives potassium ion in aqueous medium and combines with hydroxide ion present in water to form potassium hydroxide where as
ions of water by gaining electrons (from potassium in water) gives hydrogen gas.
Hence , yes it is a redox reaction
Combustion reaction are the chemical reaction in which one reactant react with oxygen molecule to give heat and light.
Here in given reaction no oxygen molecule is appearing on reactant side.
Hence not a combustion reaction.
When a 0. 1 m aqueous solution of hydrocyanic acid, HCN, reaches equilibrium, the ka for hydrocyanic acid is 3.969 x 10⁻¹⁰.
<h3>What is ka value?</h3>
It's the value of equilibrium constant for the dissociation of ions into a solution. The more the Ka value the more will be dissociation.
Ka = [H₃O⁺]² / [HCN] [H₃O⁺]
The pH is 5.20
-log [H₃O⁺] = 5.20
Putting antitlog both side.
The value will be 6.30 x 10⁻⁶
Ka = (6.30 x 10⁻⁶)² / 0.1 - 6.30 x 10⁻⁶
0.1 - 6.30 x 10⁻⁶ = 0.1
Ka = 3.969 x 10⁻¹⁰
Thus, the Ka value for hydrocyanic acid is 3.969 x 10⁻¹⁰.
To learn more about ka value, refer to the link:
brainly.com/question/2796803
#SPJ4