Chemistry

• Nucleus has protons and neutrons
• Neutrons have a charge of 0
• Neutrons have a mass of 1
• Protons have a mass of 1
• Electrons have a mass of 0/very small
• Elections have a -1 charge
• Protons have a +1 charge
• Electrons orbit the atom on shells
• every Atom has the same number of electrons as it does protons
• an ion is an atom with a charge
• Copper can conduct electricity because it has delocalised electrons that can move through the structure and carry a current
• compounds are substances that are made up of two or more elements chemically combined
• A mixture is a substance that contains two or more elements or compounds that are not chemically combined
• Chromatography is used to separate mixtures of substances that are soluble in the solution
• A solvent is a liquid that can dissolve a substance.
• A solution is a mixture of two or more substances that are dissolved in each other.
• A solute is a substance that is dissolved in a solvent.
• Filtration is A method of separating insoluble solids from a solution
• John dalton first Described atoms to be split spheres
• JJ Thompson created the plum pudding model which was negative electrons floating in positive charge
• Ernest Rutherford conducted the alpha particle experiment where they fired positively charged Alpha particles expecting them to pass straight though.
• Rutherford discovered the nucleus
• Bohr discovered shells
• Atoms react when they have a full outer shell and form an ion
• Mendeleev left gaps in his table to leave room for future elements
• Mendeleev arranged His periodic table in order of atomic mass, with the heaviest elements at the bottom
• Mendeleev grouped together elements with similar properties
• Group 1 metals are also Known as the alkali metals.
• Group 7 metals are also knows has the halogens. They are very reactive and can be used in batteries.
• Group 0 are known as the noble gasses
• Metals are elements that form positive Ions
• metals Are strong whilst non metals are weak
• Metals are shiny whilst non metals appear dull
• Metals have high melting and boiling points which is due to the strong forces of attraction between the delocalised electrons
• Non metals have low boiling points and low melting points. They are brittle and have low densities.
• Transition metals are good catalysts because they have high melting points and high boiling points
• Transition metals are often various colours
• There are no specific trends in the reactivity of transition metals
• Metals are able to conduct electricity whilst non metals can’t
• As you go down group 7, the reactivity decreases