Specification Point 1.46:
Understand how to use dot-and-cross diagrams to represent covalent bonds in: • diatomic molecules, including hydrogen, oxygen, nitrogen, halogens and hydrogen halides • inorganic molecules including water, ammonia and carbon dioxide • organic molecules containing up to two carbon atoms, including methane, ethane, ethene and those containing halogen atoms

Covalent Compound: Compound with bonds between Non-Metal and Non-Metal formed by the shared pair of electrons between the two atoms

DOT-AND-CROSS DIAGRAMS OF DIATOMIC MOLECULES:

Hydrogen

Dot & cross of Hydrogen, CIE IGCSE Chemistry

Oxygen

Dot & cross of Oxygen, Edexcel IGCSE Chemistry

Nitrogen

Dot & cross of Nitrogen, CIE IGCSE Chemistry

Fluorine

Dot & Cross of Fluorine, Edexcel IGCSE Chemistry

Chlorine

Dot & cross of Chlorine, CIE IGCSE Chemistry

Bromine

Dot & cross of Bromine Edexcel IGCSE Chemistry

Iodine

Dot & cross of Iodine, Edexcel IGCSE Chemistry

Astatine

Dot & cross of Astatine, Edexcel IGCSE Chemistry

DOT-AND-CROSS DIAGRAMS OF INORGANIC MOLECULES:

Water

Dot & cross water, CIE IGCSE Chemistry

Ammonia

Dot & cross ammonia, CIE IGCSE Chemistry

Carbon Dioxide

Dot & cross carbon dioxide, CIE IGCSE Chemistry

DOT-AND-CROSS DIAGRAMS OF ORGANIC MOLECULES:

Methane

Dot & cross methane, CIE IGCSE Chemistry

Ethane

Dot & cross Ethene, Edexcel IGCSE Chemistry

Ethene

Dot & cross Ethane, CIE IGCSE Chemistry

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Author: Jamie

Jamie got a First class degree in Chemistry from Oxford University before going on to teach chemistry full time as a professional tutor. He’s put together these handy revision notes to match the Edexcel IGCSE Chemistry specification so you can learn exactly what you need to know for your exams.