atoms, elements, compounds and mixtures Flashcards
(16 cards)
what is an atom
the smallest part of an element that can exist
what is an element
a substance that contains only 1 type of atom
what is a compound
contains 2 or more elements that are chemically combined
how can compounds be separated
chemical reactions or electrolysis
how is an element different to a compound
elements contain only 1 type of atom and compounds contain 2 or more types of atoms that are chemically combined
what are reactants
the substance that reacts (left side of equation)
what are products
the new substance formed (right side of thr equation)
why is the total mass of reactants in a chemical reaction always equal to the the total mass of products?
atoms are not made or lost during a reaction
when copper metal is heated it reacts with oxygen, what is the product
copper oxide
what is a mixture and do they retain their own properties
contains 2 or more elements or compounds that are not chemically combined, They retain their own properties
eg: a mixture of iron and sulfur, the iron is still magnetic and sulfur is still yellow
what are 3 methods that can separate mixtures
filtration, crystallisation, simple distillation, fractional distillation, chromatography
what is filtration
used to separate soluble solids from insoluble solids using filter paper
what is crystallisation and explain the process
what - used to obtain a soluble solid from a solution
explanation - mixture is gently warmed, and water evaporates forming crystals
what is distillation and explain
what- used to separate liquid from a solution
explain- liquid boils and condenses into condenser. thermometer reads boiling point of pure liquid
what is fractional distillation
separates mixtures with different boiling points
what is chromatography
separates different soluble colours of a mixture
eg- different colours in a fizzy drinks can be separated into different colours
