Yes! You're correct! Hope this helps! :D
<u>Answer:</u> The value of
for the net reaction is 
<u>Explanation:</u>
The given chemical equations follows:
<u>Equation 1:</u> 
<u>Equation 2:</u> 
The net equation follows:
As, the net reaction is the result of the addition of first equation and the second equation. So, the equilibrium constant for the net reaction will be the multiplication of first equilibrium constant and the second equilibrium constant.
The value of equilibrium constant for net reaction is:

We are given:


Putting values in above equation, we get:

Hence, the value of
for the net reaction is 
a. ELEMENT: A substance<span> that </span>cannot<span> be decomposed (</span>broken down<span>) </span>into simpler substances by ordinary chemical<span> means.</span>
Answer:
No reaction
Explanation:
Single-displacement reaction is the chemical reaction in which one metal which has higher negative redox potential replaces the another from it's salt solution.
Thus, Cu cannot replaces zine from its salt as it is less reactive than zince.
However, zinc can replace copper from its salt as:

Periodic table is arranged according to atomic size and other properties.