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Lustrous (shiny)
Good conductors of heat and electricity.
High melting point.
High density (heavy for their size)
Malleable (can be hammered)
Ductile (can be drawn into wires)
Usually solid at room temperature (an exception is mercury)
Opaque as a thin sheet (can't see through metals)
Answer:

Explanation:
We can use the formula for momentum to calculate the mass.

Explanation:
In an ionic compound, there will be strong force of attraction between the combining atoms due to the opposite charges present on them.
For example,
is an ionic compound where calcium has a +2 charge and each bromine atom has a -1 charge.
Therefore, in order to break the bond we need to provide more heat. Hence, boiling point of calcium bromide will be the highest.
is a covalent compound and as nitrogen is more electronegative in nature and also has a lone pair of electron hence, there will be a net dipole moment.
is also a covalent compound. And, as bromine is more electronegative than carbon atom so, dipole moment is in the outwards direction. Hence, in
there will be zero dipole moment.
Therefore, its boiling is less than the boiling point of
.
is a covalent compound and there will be no dipole moment.
Thus, we can conclude that given bromine-containing compounds are placed in their increasing boiling point order as follows.
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