Predict the formula of the stable binary compounds formed by the combination of the following pairs of elements.
(a). Lithium and oxygen (b) magnesium and nitrogen (c) phosphorus and fluorine.

Which of the following pair of elements form a compound with maximum ionic character ?

Transition elements form binary compounds with halogens. Which of the following elements will form MF_(3) type compounds -

The pair of elements which on combination are most likely to form an ionic compound is

Mention the standard states of the following elements at 25^(@)C and 1atm : carbon, bromine, iodine, sulphur, oxygen, calcium, chlorine, fluorine and nitrogen.

Which element of the following pairs of elements has higher ionisation energy? Justify your answer a) K or Ca b) Be or B c) I or Ba d) F or Cl e) N or O

Which element of the following pairs have smaller ionization enthalpy? (a) Ca or Be , (b) Ca or K , (c) Cl or I. Justify your answer.

Mention the type of semiconductor (n-type or p-typr) that is formed when germanium is doped with each of the following elements. (a) Al (b) Sb ( c) B (d) As

A compound on analysis gave the following percentage composition: Na=14.31% S = 9.97%, H = 6.22%, O = 69.5%, calcualte the molecular formula of the compound on the assumption that all the hydrogen in the compound is present in combination with oxygen as water of crystallisation. Molecular mass of the compound is 322 [Na = 23, S = 32, H = 1, 0 = 16].

The molecular formula of the compound formed between B and C will be [B and C are the member of group 15 and group 17 respectively]