D. F
Molecules are a group of bonded atoms but Fluorine stands on its own
Answer:
Empirical formula is Cr₂O₃.
Explanation:
Given data:
Percentage of Cr = 68.4%
Percentage of O = 31.6%
Empirical formula = ?
Solution:
Number of gram atoms of Cr = 68.4 / 52 = 1.3
2
Number of gram atoms of O = 31.6 / 16 = 1.98
Atomic ratio:
Cr : O
1.32/1.32 : 1.98/1.32
1 : 1.5
Cr : O = 1 : 1.5
Cr : O = 2(1 : 1.5)
Empirical formula is Cr₂O₃.
The correct answer is (A) from 2nd to 3rd shell.
The explanation :
when a gain of energy is the shift of the electrons from a shell of low energy to the shell of high energy
and we have here 2nd shell is the shell of low energy, and 3rd shell is the shell of high energy.
∴ (A) from 2nd to 3rd shell is the correct answer.