Dot and cross diagrams show how electronSubatomic particle, with a negative charge and a negligible mass relative to protons and neutrons. are shared in covalent bondA bond between atoms formed when atoms share electrons to achieve a full outer shell of electrons.. The table shows dot and cross diagrams for an element, chlorine, and two compounds.
Question
Deduce the formula of water using information from the table above.
The dot and cross diagram shows that a water molecule is made up of one oxygen atom joined to two hydrogen atoms, so the formula of water is H2O.
Double and triple bonds
Some moleculeA collection of two or more atoms held together by chemical bonds. contain a double bondA covalent bond resulting from the sharing of four electrons (two pairs) between two atoms., which consists of two shared pairs of electrons. For example, oxygen molecules consist of two oxygen atoms joined together. Oxygen atoms can form two covalent bonds, so to link the two oxygen atoms together, a double bond forms between them.
A nitrogen molecule is made up of two nitrogen atoms joined together. Nitrogen atoms can form three covalent bonds, so a triple bond forms between them. The structure of nitrogen is N≡N, showing that it has three shared pairs of electrons.
Question
Give the structure of an oxygen molecule, using one line to represent each shared pair of electrons.