Chemistry

• Metallic bond= The attraction between positive metal ions and delocalised electrons within a metallic lattice structure.
• Electrolyte= A substance that conducts electricity when dissolved in water
• Ionic bond= A strong electrostatic force of attraction between oppositely charged ions, formed when one atom has lost or gained an electron to become an ion.
• Covalent bond= a chemical bond formed between two non-metal atoms by the sharing of electrons
• Alkali metals=group one, react with water to form hydroxide ions
• Noble gases= group zero, unreactive elements which have full outer shells
• Halogens= group seven, reactive elements which readily gain an electron to form negative ions
• avogadro’s constant=the number of moles,molecules or ions in a substance
• cation=positive ion
• anion=negative ion
• conservation of mass=no atoms are lost or gained during a chemical reaction
• limiting reactant=reactant that is completely used up first
• Diamond=giant covalent structure made up of strong carbon bonds with 4 other carbons
• Fullerene’s=Molecules of carbon with hollow shapes, they are very stable and can conduct electricity
• Graphite= 2 layers of carbon atoms bonded together in a hexagonal lattice,form 3 covalent bonds with other carbon atoms
• graphene=layer of graphite,good conductivity
• Reduction=gain electrons/lose oxygen
• Oxidation= gain of oxygen, loss of electrons
• intermolecular forces=forces between molecules,strength of these impacts boiling point/melting point
• lattice=a repeating pattern of atoms or molecules held together by strong covalent bonds
• mass number=total number of neutrons and protons
• subatomic particles=particles smaller than an atom. electrons, protons, neutrons
• simple molecules=molecules containing a fixed number of atoms covalently bonded together
• acid= H+ ions in solution,pH of 0-7
• neutralisation reaction=when an acid reacts with an alkali to form salt and water
• alloy=Metal compound made from 2+ metals together
• atomic number= number of protons
• isotopes=same element with different number of neutrons and same amount of protons