There is no "generally". For alkali metals (group 1) and alkali earths (group 2) they decrease. For groups 4 to 10 they rise, for group 11 it goes down from copper to silver and then up to gold.
The melting point decreases because:
Melting points are the temperatures at which metals begin to melt. They decrease as the forces of attraction between atoms get weaker.
Down in the group the atomic radius is greater and as a consequence the metallic bond is weaker.
Alkali metals have relatively low melting points compared to the other metals. Their exact melting points depend on the element itself. But it would be useful to note that their melting points decreases down group I.
The melting and boiling points increase down the group because of thevan der Waals forces. The size of the molecules increases down the group. This increase in size means an increase in the strength of the van der Waals forces.
Melting Point
As we move down the group, the melting point decreases.
The boiling points of noble gases increases down a group.
The melting point is greater.
Alkali metals have relatively low melting points compared to the other metals. Their exact melting points depend on the element itself. But it would be useful to note that their melting points decreases down group I.
The melting point of magnesium is 650 degrees celcius. It has the lowest melting point among all the group II metals (alkaline earth metals), though the melting points generally decrease down the group - magnesium is an exception and has the lowest melting point among them.
Melting points generally decrease as you go down a group for group I and group II metals. This does not apply to the transition metals. Reactivity of metals increases down a group due to a larger size and less effective charge between the nucleus and valence electrons. Atomic radius increases due to a higher principle number of electrons.
The melting and boiling points increase down the group because of thevan der Waals forces. The size of the molecules increases down the group. This increase in size means an increase in the strength of the van der Waals forces.
Yes, transition metals have higher melting points. This is due to having very strong bonds. This means that a larger amount of energy is needed in order to break them down or bring them to the melting points.
Melting Point
Ionic compounds generally have higher melting and boiling points.
As we move down the group, the melting point decreases.
They have low melting and boiling points which increases down the group. They form diatomic molecules They form simple ions with -1 charge They react with hydrogen to form acidic compound
a lower melting point and a lower boiling point since the effective nuclear charge decreases going down a group therefore the amount of force needed to repel the electrons from the protons is weaker.
The boiling points of noble gases increases down a group.