Q1
What is wrong with each of the following attempts to write an electron
configuration? Justify your answer with suitable explanation.
(a) 1s22s3
(b) 1s22s22p23s2
(c) 1s22s23s2
(d) 1s22s22p63s23d10
[5]
Q2 Given the following percent compositions, determine the empirical
formula.
(a) 47.26% Cu, 52.74% Cl
(b) 40.27% K, 26.78% Cr and 32.96% O
[5]
Q3 Discuss the classification of elements in the periodic table.
[5]
Q4 Explain different types of chemical bonds. [5]
Q5 Explain with the mechanism how the following buffer solutions maintain
fairly constant pH, even when a small amount of acid or alkali is added
to it.
(a) Acidic buffer (CH3COOH + CH3COONa) and
(b) Basic buffer (NH4OH + NH4Cl)