Hi!
The correct option would be A.
This is because the displacement reaction would take place as follows
Ca + ZnCl2 --> CaCl2 + Zn
A displacement reaction is one in which a substitution occurs, as the more reactive element in the mixture replaces one that is less reactive.
In the electrochemical series, we find Ca higher than Zn, which is indicative of Ca being more reactive, and having the capacity to displace Zn to form a compound.
Option D would be incorrect as no such substitution occurs.
Option B would be incorrect because again, there is no substitution occurring, and also because two metals alone (Ca and Zn in our case) can never react to form a compound.
Option C would be incorrect because it is not possible because CaCl and ZnCl are forms that are too unstable to exist due to an overall positive charge.
Hope this helps!
<h2>Hardness, lustre, and colour.</h2>
Explanation:
These Rocks shown in photographs are made of different types of minerals which have properties as follows:
●The color of the rock is grey, brown and yellow after it is ground into a powder its color is streak.
● The lustre of the rock tells how shiny the rocks are.
● Other properties include hardness, texture, shape, and size.
Answer: Natural selection.
Explanation:
The natural selection is the process by which the organism that best suits the characters will survive and the organism which cannot adapt the changes will die.
The predators feed on their prey and the organism which hides easily in the environment due to its color is safe and the animals that cannot camouflage will die.
This is natural selection that more favored character is carried out over generations and other that cannot survive die.
