<u><em>Answer:</em></u>
- The correct option is C.
- Formation of a precipitate
<u><em>Explanation:</em></u>
During a chemical reaction, new substances are formed known as a products, mostly reaction occur and their product is obtained as precipitates.
<u><em>Example</em></u>
Arylidene-2-thiobarbituric acid is obtained as precipitates when aldehyde and thiobarbituric acid react to each other.
melting of a substance
It is just indication of physical changes, like melting of ice, composition remained same as before.
boiling of a substance
It is just indication of physical changes, like boiling of water into vapors, composition remained same as before.
freezing of a substance
It is just indication of physical changes, like freezing of water into ice, composition remained same as before
It is called rust and it forms when water soaks into the metal forming a chemical reaction.
Answers:
Density = 0.8 g/mol.
Given data:
v = 25 ml
m = 20 g
δ = ?
Solution:
Formula for calculating density is given as,
Density = Mass / Volume
putting values
Density = 20.0 g / 25 ml
Density = 0.8 g/mol.