Atom: its the smallest
indivisible (can't divide)
particle.
Element: something
thats made up of one
kind of atom.
Compound: when different
kinds of atoms are put
together.
Mixture: different compounds
put together but not connected /
touching / do not react together.
The nucleus of an atom
is made of protons and
neutrons.
The atomic number (or proton number)of
an element is equal to the number of
protons in the nucleus of its atoms
eg: fluorine - atomic number: 9 - mass number: 19
number of protons = atomic number =9
number of electrons = number of protons = 9
number of neutrons = 19 - 9 = 10
The mass number is the sum of
the protons and neutrons in the
nucleus of an atom.
LIMESTONE
used to make Calcium Oxide and Cement.
make Concrete by mixing sand, aggregate, and
water.
Calcium Carbonate (CaCO30 decomposes when
heated to make Calcium Oxide (CaO) and Carbon
Dioxide (CO2) : Thermal Decomposition
equation : CaCO3 -> CaO + CO2
LIMESTONE CYCLE
REACTIONS OF CARBONATES
Metal + Non-Metal = ion
metal atoms lose one or more electrons to form positively charged
ions. Non-Metal atoms gain electrons to form negatively charged
ions.
All Metal Carbonates decompose to the Metal
Oxide and Carbon dioxide when they are
heated strongly enough .
Carbon Hydroxide
solution is called
Limewater.
Limewater turns cloudy when
it reacts with carbon dioxide to
produce insoluble calcium
carbonate.
AIR POLLUTION
PARTICULATES
cause: Burning fossil
fuels and wood.
particulates vary in
composition and size.
effects: fine particulates
can get into lungs
causing breathing
difficulties. They make
cars and buildings dirty.
CARBON MONOXIDE
Cause: incomplete combustion of
fossil fuels. This can happen in faulty
gas appliances and road traffic.
Effect: Carbon Monoxide is very
dangerous because it decreases the
ability of the blood to carry oxygen. If
untreated, this can lead to death.
SULFUR DIOXIDE
Cause: power stations burning
fossil fuels containing sulfur.
Effects: Sulfur Dioxide is an
acidic gas that can combine
with water vapour in the
atmosphere to cause rain.
Breathing Sulfur Dioxide can
cause respiratory proble
Properties and uses of Alloys
in a pure metal the atoms are
stocked in layers and when a force is
applied the layers slide easily.
in an alloy there are different
sized atoms in the structure and
when a force is applied, the layers
can't move easily because of the
different sized atoms blocking and
jamming up the structure.
bolts and hinges aren't made from
pure brass and copper because they
are too soft on their own . Copper has
to be mixed with other metals in order
to be strong enough.
properties of a
metal: shiny,
good electrical
conductor
EXTRACTING METALS
rock that contains enough of a metal or a metal
compound to make it worth extracting the metal
is called an ORE.