Chemistry Flashcards
Isotopes
atoms of the same element with a different number of neutrons
Exothermic
when energy is transferred to or from the surroundings.
Endothermic
when energy is taken in from the surroundings.
Exothermic examples
combustion reactions, many oxidation reactions, most neutralisation reactions
Endothermic examples
thermal decomposition reaction, the reaction of citric acid and sodium hydrogencarbonate.
Acids
substances that form hydrogen ions when dissolved in water.
Alkalis
substances that form hydroxide ions when dissolved in water.
Oxidation
a reaction which involves gaining oxygen, (involves losing electrons.)
Reactive metals react with cold water
Hydrogen gas and metal hydroxide is produced.
Reactivity series
Please -Potassium
Stop - Sodium
Calling - Calcium
Me - Magnesium
A - Aluminium
Careless - Carbon
Zebra - Zinc
Instead - Iron
Try - Tin
Learning - Lead
How - Hydrogen
Copper
Saves - Silver
Gold
Acids react with carbonates
makes salt, water and carbon dioxide.
Giant covalent structure
a structure in which very large numbers of atoms are joined together by covalent bonds.
Fullerenes
molecules made up of carbon atoms with hollow shapes.
Examples of giant covalent structure
diamond and graphite.
Examples of fullerenes
buckministerfullurene and nanotubes.
Graphene
single layer of graphite, the strong covalent bonds between the carbon atoms means that the graphene has a high melting point and is very strong.
Graphite properties
high melting and boiling point, good electrical conductivity, soft.
Metals that react with dilute acids
magnesium, aluminium, zinc, iron and lead.
Metals that don’t react with dilute acids
copper, silver, gold and platinum.
Titration
measures the volume of acid and alkali solution needed in a neutralistaion reaction.
Cathode
Negatively charged electrode.
Anode
Positively charged electrode.
Cation
Positively charged ion.
Anion
Positively charged electrode.
