AQA GCSE Chemistry Paper 1 || solved correctly.
What is an *atom*? correct answers smallest part of an element
What is an *element*? correct answers a substance that contains only one type of atom
What are *chemical symbols*? correct answers - the letter or pair of letters that represents an
element.
- first letter is always capitalized
What are *compounds*? correct answers substances in which atoms of two or more elements,
which are chemically combined
What is a *chemical formula*? correct answers a combination of symbols that shows the ratio of
elements in a compound
Why are *chemical formula* used? correct answers - the different elements in a compound
- how many atoms of each element one molecule of the compound contain
How can *compounds* be separated? correct answers Through chemical reactions
What are *reactants*? correct answers the starting materials in a chemical reaction (on the left)
What are *products*? correct answers the ending materials in a chemical reaction (on the right)
What is always *equal* to each other in a *chemical reaction*? correct answers products to
reactants
- no atoms are lost or made
,What is a *mixture*? correct answers consist of two or more elements or compounds which are
not chemically combined
What are the *properties* of *mixtures*? correct answers they retain their own properties from
before
e.g. colour
How can *mixtures* be separated? correct answers by physical processes - no new substances
are made
What is *filtration*? correct answers - used to separate soluble solids from insoluble solids
What is *crystallisation*? correct answers - used to obtain a soluble solid from a solution
1. Mixture is gently warmed
2. Water evaporates leaving crystals of pure salt
What is *simple distillation*? correct answers used to obtain a solvent from a solution
*RP* Analysis and purification of water samples from different sources correct answers 1. Use a
pH probe or indicator to analyse the pH of the sample
2. Set up the equipment
3. Heat a set volume to 100oC so that the water changes from liquid to gas
4. Water collects in the condenser and changes state from gas to liquid
5. measure the mass of solid that remains to find the amount of dissolved solids present in the
sample
What is *fractional distillation*? correct answers - used to separate mixtures in which the
components have different boiling points
,What is *chromatography*? correct answers used to separate the different soluble, coloured
components of a mixture
What were *atoms* thought to be in *early models*? correct answers Tiny spheres that could not
be divided into simpler particles
What did *Thomson* discover in 1898? correct answers electrons - causing the representative of
atoms to be changed
What model did *Thomson* make ? correct answers plum pudding model
What was the *plum pudding* model made up of? correct answers - atom contained tiny,
negative electrons
- surrounded by a positive charge
What did *Geiger and Marsden* do? correct answers measured the deflection of alpha particles
bombarding gold foil
What did *Geiger and Marsden* conclude about their experiment? correct answers - some alpha
particles deflected
- some went straight through
What did *Rutherford* conclude about the *alpha and gold foil* experiment? correct answers -
there must be a positive charge in the center of each atom (new model now called 'nuclear')
What did *Bohr* do? correct answers said that electrons were arranged in levels or orbits around
the nucleus
What did *James Chadwick* discover? correct answers neutrons in the nucleus
, How big are *atoms*? correct answers - very small
- 0.1nm or 1 x 10^-10m
What do all *atoms* contain? correct answers protons, neutrons, electrons
What is the *relative charge* and *mass* of a *proton*? correct answers 1
+1
What is the *relative charge* and *mass* of a *nucleus*? correct answers 1
0
What is the *relative charge* and *mass* of an *electron*? correct answers very small
-1
Where is most of the *mass* of an *atom*? correct answers nucleus
How much *smaller* is the radius of the *nucleus* compared to the rest of the atom? correct
answers 1/10000
Why do *atoms* have no *overall charge*? correct answers they contain an equal number of
protons and electrons
What do all atoms of a particular *element* have in common? correct answers - they have the
same number of protons
What is the *atomic number*? correct answers number of protons
What is an *atom*? correct answers smallest part of an element
What is an *element*? correct answers a substance that contains only one type of atom
What are *chemical symbols*? correct answers - the letter or pair of letters that represents an
element.
- first letter is always capitalized
What are *compounds*? correct answers substances in which atoms of two or more elements,
which are chemically combined
What is a *chemical formula*? correct answers a combination of symbols that shows the ratio of
elements in a compound
Why are *chemical formula* used? correct answers - the different elements in a compound
- how many atoms of each element one molecule of the compound contain
How can *compounds* be separated? correct answers Through chemical reactions
What are *reactants*? correct answers the starting materials in a chemical reaction (on the left)
What are *products*? correct answers the ending materials in a chemical reaction (on the right)
What is always *equal* to each other in a *chemical reaction*? correct answers products to
reactants
- no atoms are lost or made
,What is a *mixture*? correct answers consist of two or more elements or compounds which are
not chemically combined
What are the *properties* of *mixtures*? correct answers they retain their own properties from
before
e.g. colour
How can *mixtures* be separated? correct answers by physical processes - no new substances
are made
What is *filtration*? correct answers - used to separate soluble solids from insoluble solids
What is *crystallisation*? correct answers - used to obtain a soluble solid from a solution
1. Mixture is gently warmed
2. Water evaporates leaving crystals of pure salt
What is *simple distillation*? correct answers used to obtain a solvent from a solution
*RP* Analysis and purification of water samples from different sources correct answers 1. Use a
pH probe or indicator to analyse the pH of the sample
2. Set up the equipment
3. Heat a set volume to 100oC so that the water changes from liquid to gas
4. Water collects in the condenser and changes state from gas to liquid
5. measure the mass of solid that remains to find the amount of dissolved solids present in the
sample
What is *fractional distillation*? correct answers - used to separate mixtures in which the
components have different boiling points
,What is *chromatography*? correct answers used to separate the different soluble, coloured
components of a mixture
What were *atoms* thought to be in *early models*? correct answers Tiny spheres that could not
be divided into simpler particles
What did *Thomson* discover in 1898? correct answers electrons - causing the representative of
atoms to be changed
What model did *Thomson* make ? correct answers plum pudding model
What was the *plum pudding* model made up of? correct answers - atom contained tiny,
negative electrons
- surrounded by a positive charge
What did *Geiger and Marsden* do? correct answers measured the deflection of alpha particles
bombarding gold foil
What did *Geiger and Marsden* conclude about their experiment? correct answers - some alpha
particles deflected
- some went straight through
What did *Rutherford* conclude about the *alpha and gold foil* experiment? correct answers -
there must be a positive charge in the center of each atom (new model now called 'nuclear')
What did *Bohr* do? correct answers said that electrons were arranged in levels or orbits around
the nucleus
What did *James Chadwick* discover? correct answers neutrons in the nucleus
, How big are *atoms*? correct answers - very small
- 0.1nm or 1 x 10^-10m
What do all *atoms* contain? correct answers protons, neutrons, electrons
What is the *relative charge* and *mass* of a *proton*? correct answers 1
+1
What is the *relative charge* and *mass* of a *nucleus*? correct answers 1
0
What is the *relative charge* and *mass* of an *electron*? correct answers very small
-1
Where is most of the *mass* of an *atom*? correct answers nucleus
How much *smaller* is the radius of the *nucleus* compared to the rest of the atom? correct
answers 1/10000
Why do *atoms* have no *overall charge*? correct answers they contain an equal number of
protons and electrons
What do all atoms of a particular *element* have in common? correct answers - they have the
same number of protons
What is the *atomic number*? correct answers number of protons
