1 and 3 only because metal are easily to loss electron while non metal are difficult to loss electron that's why it called heavy elements.
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A link to this experiment is below in the comment box
By sharing electeons with each other
if they lose or gain electrons then they only form ions
they cannot lose neutrons as they are locked inside the nucleus
Answer : The change in boiling point is, 
Explanation :
Formula used :
where,
= change in boiling point = ?
i = Van't Hoff factor = 3 (for MgI₂ electrolyte)
= boiling point constant for water = 
m = molality = 0.615 m
Now put all the given values in this formula, we get
Therefore, the change in boiling point is,
