GCSE Chemistry Structure and Bonding Flashcards
Structure and Bonding
Give the 4 state symbols and state what they stand for.
We use state symbols to represent the different states in chemical equations. The state symbols are:
Solid (s)
Liquid (l)
Gas (g)
Aqueous (dissolved in water) (aq)
What is a compound?
A compound is a substance made up of 2 or more elements which have chemically combined.
Name the 3 types of strong chemical bonds?
There are 3 types of strong chemical bonds: ionic, covalent and metallic.
Between which types of elements do ionic bonds form?
Ionic bonds are formed between metals and non-metals.
What types of ions will metal elements form?
Metal atoms will lose electrons to become positive ions and to have a stable full outer shell of electrons.
What types of ions will non-metal elements form?
Non-metal atoms will gain electrons to become negative ions and have a full outer shell of electrons.
Why would an atom gain or lose electrons?
Atoms will gain or lose electrons to achieve a full outer shell
How do ionic bonds form?
To form an ionic compound electron transfer takes place. Electrons move from a metal to a non-metal.
Name the forces that hold ions together in an ionic bond.
Ions are held together in ionic compounds by electrostatic forces of attraction between the positively charged metal ion and the negatively charged non-metal ion.
What type of diagram do we use to represent electron transfer?
Electron transfer during the formation of an ionic compound can be represented by a dot and cross diagram.
What is the overall charge on an ionic compound?
Ions combine so that the overall charge on the compound is zero.
What makes a crystal lattice strong?
Each ion is surrounded by oppositely charged ions in all directions making the structure very strong.
What types of elements form covalent bonds?.
Covalent bonds form between non-metals.
How do atoms achieve a full outer shell of electrons through covalent bonding.
In a covalent bond non-metal atoms share pairs of electrons with other non-metal atoms to achieve a full outer shell.
What does each shared pair of electrons represent?
Each shared pair of electrons represents a covalent bond.
What forces act between small covalent molecules?
Weak intermolecular forces act between small covalent molecules.
Why do small covalent molecules have low melting and boiling points?
Weak intermolecular forces do not require much energy to break so small covalent molecules have low melting and boiling points.
Give 7 examples of small covalent molecules.
Examples of small covalent molecules include: HCl, H2O, H2, O2, Cl2, NH3 and CH4
