c1 Flashcards
(23 cards)
what isthe relationship between metals and ions.
Candidates should know that metals lose electrons to
form positive ions, whereas non-metals gain electrons to
form negative ions. Knowledge of such transfers is
limited to single electrons
Aluminium and titanium cannot be extracted from
their oxides by reduction with carbon. Current
methods of extraction are expensive because:
■ there are many stages in the processes
■ large amounts of energy are needed.
why is the blast furnace used.
blast furnace iron being used as cast iron because of its
strength in compression.
what are high carbonsteels
low carbon
stainless steels?
s. Low-carbon
steels are easily shaped, high-carbon steels are
hard, and stainless steels are resistant to corrosion.
name the properties of transition metals
they are good conductors of heat and
electricity and can be bent or hammered into
shape. They are useful as structural materials
and for making things that must allow heat or
electricity to pass through them easily
copper does not react with water-true/false
true
what is a mixture
A mixture consists of two or more elements or
compounds not chemically combined together.
The chemical properties of each substance in
the mixture are unchanged. It is possible to
separate the substances in a mixture by
physical methods including distillation
what happens during the combustion of hydrocarbon fuels
The combustion of hydrocarbon fuels releases
energy. During combustion the carbon and
hydrogen in the fuels are oxidised.
descrobe the process of cracking
Hydrocarbons can be cracked to produce smaller,
more useful molecules. This process involves heating
the hydrocarbons to vaporise them. The vapours are
either passed over a hot catalyst or mixed with steam
and heated to a very high temperature so that thermal
decomposition reactions then occur
what doemulsifiers provide
They provide better texture, coating
ability and appearance, for example in salad dressings,
ice creams, cosmetics and paints
what are vegtable oils
Vegetable oils that are unsaturated contain double
carbon–carbon bonds. These can be detected by
reacting with bromine water
how are vegtable oilshardened for usein foods
Vegetable oils that are unsaturated contain double
carbon–carbon bonds. These can be detected by
reacting with bromine water
what are the three main parts of the earths crust
core, mantle and crust
describe the earths mantle
Convection currents within the Earth’s mantle driven
by heat released by natural radioactive processes
cause the plates to move at relative speeds of a
few centimetres per year
how are earthquakes formed
The movements can be sudden and disastrous.
Earthquakes and / or volcanic eruptions occur at
the boundaries between tectonic plates.
how much nitrogeon and oxygen is in the air
■ about four-fifths (80%) nitrogen
■ about one-fifth (20%) oxygen
how were the oceans formed in the early atmosphere
During the first billion years of the Earth’s existence
there was intense volcanic activity. This activity
released the gases that formed the early atmosphere
and water vapour that condensed to form the oceans
was there oxygen at the start of the world
no
what was the miller-urey theory
One theory as to how life was formed involves
the interaction between hydrocarbons,
ammonia and lightning.
what do plants andalgae do in the earths atmosphere
plants and algae
produce oxygen by a process called photosynthesis
and that this process uses carbon dioxide from the
atmosphere.
what mostly happens to c02 in the air
carbon dioxide dissolves
in the oceans and that limestone was formed from the
shells and skeletons of marine organisms. Fossil fuels
contain carbon and hydrocarbons that are the remains
of plants and animals.
what do theoceans do for c02
The oceans also act as a reservoir for carbon dioxide
but increased amounts of carbon dioxide absorbed
by the oceans has an impact on the marine
environment
describe air
Air is a mixture of gases with different boiling
points and can be fractionally distilled to provide
a source of raw materials used in a variety of
industrial processes.
