Periodic Trends Quiz

Study Notes

The periodic table arranges elements by atomic number, with similar properties grouped together. Periods are rows, and groups are columns.
Elements in the same period have the same number of electron shells. Elements in the same group have the same number of electrons in their outermost shell, leading to similar properties.
Group 1 elements become more reactive as you move down the group, Group 7 elements gradually become less reactive.
Metals have higher melting points but increasing metallic bonding strength for the metals in periods 2 and 3.
Melting points for molecular substances depend on the strength of intermolecular forces, which are usually weak. Larger molecules have stronger intermolecular forces.
Noble gases have the lowest melting points due to weak intermolecular forces since they exist as individual atoms.
Period 2 and 3 elements exhibit similar trends in melting points. Trends are linked to structure and changes in bond strength.
Metallic bonding is stronger when metals have more delocalized electrons, decreasing ionic radius and higher charge density, which attracts ions more strongly.
Covalent bonding in giant covalent structures requires a lot of energy to break and results in very high melting points.

Melting points of elements tend to increase across a period for metals (periods 2 and 3).
Melting points of elements tend to decrease across a period for non-metals (periods 2 and 3).
Simple molecular substances have relatively low melting points.
The strength of intermolecular forces increases with the size of the molecule in molecular substances.
Noble gases exist as individual atoms, resulting in very weak intermolecular forces. This leads to a low melting point as the intermolecular forces are weak.