3.1.3 - pure substance Flashcards
what do pure substances contain?
only ONE type of particles
pure substance melting+ boiling point?
have a single sharp melting and boiling point
what do mixtures contain?
different types of particle
mixtures melting + boiling point?
melt and boil over a range of temperatures
what is an element?
a substance containing only one kind of atom
what is a compound?
a substance containing different types of atoms which are chemically bonded together
chemical test for water?
anhydrous copper(II) sulphate
turns white -> blue
physical tests for water?
melting point = 0 degrees
boiling point = 100 degrees
pure water would melt/boil exactly on this temp
properties of metals:
- high MP/BP
- electrical conductors
- malleable
- shiny
- form alkaline oxides
properties of non-metals:
- low MP/BP
- electrical insulators
- brittle
- dull
- form acidic oxides
what is element combustion?
when an element reacts with oxygen to produce an oxide
element combustion equation?
element + oxygen -> element oxide
combustion of magnesium equation?
magnesium + oxygen -> magnesium oxide
2Mg + O2 -> 2MgO
observations of combustion of magnesium?
bright white light
white powder formed
combustion of sulphur equation?
sulphur + oxygen -> sulphur dioxide
S + O2 -> SO2
observations of combustion of sulphur?
blue flame
combustion of hydrogen equation?
hydrogen + oxygen -> water
2H2 + O2 -> 2H2O
observations of combustion of hydrogen?
squeaky pop
when metal oxides dissolve in water do they form an acidic or alkaline solution?
alkaline
when non-metal dioxides dissolve in water do they form an acidic or alkaline solution?
acidic
what bonding happens between metals?
metallic bonding
what bonding happens between non-metals?
covalent bonding
what bonding happens between metals and non-metals?
ionic bonding
