what are Non-stoichiometric compounds?

Among the following, the non - stoichiometric compounds are -

Give an example of a non-stoichiometric compound.

What are non-stoichiometric hydrides ? Give examples.

What are non-stoichiometric defects? Give two example of such defects.

Analyses shows that FeO has a non-stoichiometric composition with formula Fe_(0.95)O_(1.00) . Give reason.

Analysis shows that FeO has a non-stoichiometric composition with formula Fe_(0.95)O . Give reason.

The non- stoichiometric compound Fe_(0.94)O is formed when x% of Fe^(2+) ions are replaced by as many 2//3 Fe^(3+) ions The value of x is:

What are non-stoichiometric defects in an ionic crystal? Explain how metal excess defects occur in an ionic crystal.

Why is FeO(s) not formed in stoichiometric composition?

Why is ferrous oxide hard to be prepared with ideal stoichiometric composition?