Magnalium is an alloy of

1. aluminium and magnesium
2. aluminium and copper
3. iron
4. copper

An element X belongs to group II A and another element Y belongs to group V A of the periodic table. Which of the following could be correct?

P. Valency of Y will be 5.

Q. Element X will have 2 valence electrons.

R. Element X belongs to group number 2

1. Only P
2. Q
3. R
4. Both Q and R

Tetraammine copper (II) sulphate dissolves in ammonia solution to give which colour?

1. Greeen
2. Pink
3. Blue
4. Yellow

Empirical formula and molecular formula are related as

1. Empirical formula = (molecular formula)_n
2. Molecular formula = (empirical formula)_n
3. Empirical formula = (molecular formula)ⁿ
4. None of the above