Answer:
An impure compound is dissolved (the impurities must also be soluble in the solvent), to prepare a highly concentrated solution at a high temperature. ... The impure substance will crystallize in a purer form because the impurities won't crystallize yet, therefore leaving the impurities behind in the solution
Answer:

Explanation:
The relation between frequency and wavelength is shown below as:
c is the speed of light having value
Given, Wavelength = 1040 nm
Also, 1 m =
nm
So,
Wavelength =
m
Thus, Frequency is:

A.92 all Uranium atoms contain the same amount of protons
Calcium carbonate will be formed which is insoluble in water.
The answer is a) K and CrO4 only.