Answer: Option (c) is the correct answer.
Explanation:
The bottom of pencil is placed at the starting point of scale. Whereas the tip of pencil depicts the end point of its length.
The bottom of pencil is at 0 mm and tip of pencil is at 18.73 mm. The appropriate amount of significant figures is 18.73 mm.
Therefore, we can conclude that out of the given options, pencil is 18.73 mm long.
<span>Photolysis and hydrolysis. These are two methods that can be used to break down a compound into simpler substances and smaller units.
Water which is used to break the bonds of molecules and split molecules is used from hydrolysis. Hydrolysis is made of three types which include;
1. salt hydrolysis.
2. acid hydrolysis.
3. Base hydrolysis.
Photolysis is well known to use energy from light to split the molecule and the same energy is referred to as photons which are used to break builds of molecules.</span>
The subscriot 2 means that in the formula there are two parts of K, and the subscript 1 (implicit) for S, indicates that there is one part of S.
This is, the formula gives the ratio of the elements K and S in the compound, which is:
2 atoms of K : 1 atom of S.
Answer: there are 2 atoms of K and 1 atom of S in a molecule of K2S.
