It is the systematic arrangement of the elements in increasing atomic number and shows periodicity in the chemical and physical properties.

It is the amount of energy released when electrons are added to an atom in a gaseous phase.

It refers to the one-half the distance measurement from the two nuclei of two adjacent atoms.

It is the energy needed to remove the valence electron of an atom.

It is the ability of an atom to attract an electron pair towards itself in a chemical bond.

Oxides of metal are mostly ______.

_____ Oxides react with both acid and bases.

Special bases called _____

are highly soluble in water.

Acids that are man-made are classified as

_____ acids.

_____ paper turn red in acid.