Chemistry Numericals

Calculate valence and core electrons of Carbon, Silicon, Nitrogen, Phosphorus, Oxygen, Sulfur, Magnesium and Calcium

Q) How many valence electrons do the following elements have-

a) Carbon and Silicon b) Nitrogen and Phosphorus c) Oxygen and sulfur d) Magnesium and Calcium

(Periodic table as a reference is provi

Calculate atomic weight of Chlorine from isotopes 35Cl and 37Cl

Question- Chlorine has two isotopes,³⁵Cl and ³⁷Cl; 75.77 % of chlorine is 35Cl, and 24.23% is 37Cl. The atomic mass of ³⁵Cl is 34.969 amu, and the atomic mass of ³⁷Cl is 36.966 amu.

Calculate number of protons and electrons in Na+, Ar, and Cl-

Question- How many protons and electrons do the following species have?

Na+ (atomic number Z=11), Ar (atomic number Z=18), Cl- (atomic number Z=17)

Solution

Calculate number of protons and neutrons from Oxygen isotopes 16O, 17O, and 18O

Calculate number of protons and neutrons from isotopes of Oxygen ¹⁶O, ¹⁷O, and ¹⁸O. The atomic number of Oxygen is 8.

Solution:

Calculate number of protons and neutrons in Nitrogen isotopes 13N, 14N, 15N, 16N, and 17N

Question: Nitrogen (Atomic Number 7) has stable isotopes (half-life greater than 1 sec) of mass numbers 13, 14, 15, 16 and 17. Calculate number of protons and neutrons in each of the isotopes of nitrogen.