COMPLETE QUESTIONS AND ANSWERS FULL
SOLUTION GRADED A+
◉ What are atoms? Answer: Atoms are the particles that make up
everything
◉ What is an element? Answer: An element is a substance in which
all the atoms are the same
◉ Where are elements shown? Answer: Elements are shown in the
Periodic table
◉ How many elements are there? Answer: There are around 118
elements
◉ What is a compound? Answer: A compound is a substance that
contain two or more elements chemically combined
◉ Describe the properties of compounds Answer: The properties of
compounds are usually different to the elements that they are made
from
,◉ What is a mixture? Answer: A mixture is a substance with
different elements or compounds not chemically combined
◉ Give an example of a mixture Answer: An example of a mixture is
sand and water as they are not chemically combined and can be
separated by physical means
◉ What is a molecule? Answer: A molecule is a substance that has
any elements chemically joined
◉ What does a chemical formula tell you about a molecule? Answer:
A chemical formula tells the elements in a molecule and the number
of atoms of each element
◉ How is a chemical formula presented? Answer: Each element
symbol starts with a capital letter, if there is a second letter it is in
lower case
◉ Give an example of a chemical formula Answer:
◉ What are state symbols? Answer: State symbols show the physical
state of the substance solid (s), liquid (l), gas (g), or dissolved in
water (aq)
,◉ Name three properties of Metals Answer: -Strong
-Good conductors of heat and electricity
-High melting and boiling points
◉ Name three properties of Non-Metals Answer: -Weak
-Bad conductors of heat and electricity
-Low melting and boiling points
◉ State the four different ways of separating mixtures Answer: Four
different ways of separating mixtures are filtration, crystallisation,
distillation or chromatography
◉ Describe the process of filtration Answer: Pour your mixture onto
the filter paper, the liquid simply passes through the filter paper into
the flask. The insoluble solid cannot pass through and so it stays on
the paper
◉ Describe the process of crystallisation Answer: Use the method of
filtration to filter off any excess soluble solid. Evaporate the mixture
then transfer the hot mixture onto a dish. Crystals are formed when
the mixture has cooled
◉ Describe the process of simple distillation Answer: First we
evaporate the mixture by heating it, the dissolved solid then
, vaporises. These vapours condense in the condenser, the dissolved
solid then flows into the beaker and liquid stays in the flask
◉ Describe the process of chromatography Answer: Take a strip of
filter paper and draw a line on the bottom of the paper. Put a small
drop of ink on the line, take a jar full of water up to the line and put
the filter paper in. As the water moves up we see different colours on
the paper these are the dyes in the ink
◉ What were the early ideas of the structure of atoms? Answer:
Early ideas of the structure of atoms stated that they are tiny
spheres that cannot be divided
◉ What is the plum pudding model? Answer: The plum pudding
model is what scientists suggested is the structure of atoms is after
the discovery of the electron
◉ Describe the plum pudding model Answer: The plum pudding
model suggested that an atom is a ball of positive charge with
negative electrons in embedded in it
◉ Describe how Rutherford carried out the gold foil experiment
Answer: Rutherford took a piece of gold foil, he then fired tiny
positive alpha particles at the gold foil