How many atoms are contained in 0.2moles of nitrogen? \([N_{A} = 6.02 \times 10^{23}]\)

The strength of metallic bonds depends on the 

When zinc is added to AgNO\(_{3}\) solution, crystals of silver forms on the zinc surface. This indicates that zinc is

The empirical formula of a compound containing 0.067mol Cu and 0.066mol O is    [Cu = 63.5, O = 16]

The change in the oxidation state of iron in the reaction represented by the equation:  \(2FeCl_{3} + H_{2}S \to 2FeCl_{2} + 2HCl + S\)  is