Exam Pick Ups Flashcards
Formula for ammonium nitrate?
NH4NO3
Two problems caused by release of sulfur dioxide into the environment?
Acid Rain
Leaches into soil causing minerals to be washed out.
Chemical equation for making carbon dioxide in the lab, using HCL and Calcium carbonate (CaCO3)
CaCO3 + 2HCL -> CaCl2 + H2O + CO2
Equation for the weakly acidic solution that is formed when carbon dioxide reacts with water?
CO2 + H2O (Half arrows) H2CO3(aq)
What is the name of the weakly acidic compound formed when carbon dioxide dissolves in water?
Carbonic acid.
Observations of Magnesium when burnt?
Ash.
Bight light flame.
Suggest what is seen from this reaction?
If nothing obvious, assume it is a gas.
Potassium hydroxide?
KOH
Test for Hydrogen?
Lit splint, should hear a squeeky pop.
Thermal decomposition of magnesium carbonate?
MgCO3 -> MgO + CO2
How would you get a pure dry carbonate sample?
(If asking method, mix, then stir)
Filter
Wash
dry by gently warming.
In the reaction of Zinc and Copper (II) Sulphate what would you see?
pink coating on the zinc.
solution becomes colorless.
Why does the student filter the mixture?
To obtain the in-soluble part or the product.
Colour of Bromine in displacement reactions?
Colourless to Brown.
Test for chlorine?
bleaches damp litmus paper, turning it white.
Test for Oxygen?
Relight a glowing splint.
Test for Hydrogen?
Squeky pop
Test for carbon dioxide?
turns lime water cloudy
Test for Ammonia?
Turns damp litmus paper blue.
Chemical test for water?
white anhydrous copper(II) sulphate, goes blue in presence of water.
testing for cations?
flame tests
cations: Copper(II) Cu2+
Blue
Cations: Iron(II) Fe2+
Sludgy Green
Cations: Iron(III) Fe3+
Reddish brown
testing for Anions: carbonates?
carbonates give off CO2 with HCL
Testing anions: sulfates?
Sulphates ions produce a white precipitate
Testing for anions: Halides?
Nitric acid and silver nitrate.
Protons in carbon 12?
6
State what is meant by the term relative atomic mass?
- The mean mass of an atom of an element.
- Compared to mass of Carbon-12.
Carbon-12 98.9% and carbon-13 1.1%?
(12 x 98.9) + (13 x 1.1) =
/100
= 12.01
Two changes that occur in the formation of an addition polymer?
- one of the bonds in the double bond breaks
- many of the monomers then join together.
Explain why cracking is important process in the oil industry?
- Produces smaller shorter molecules
- smaller molecules more useful as have a greater demand.
- Produces alkenes.
- smaller shorter molecules burn better and are used to make fuel.
Movement of gasses in a tube?
Diffusion
How can higher temp change the time taken in a reaction?
- Less time
- particles have more kinetic energy.
- Particles and gas move quicker and diffuse quicker.
How many bonds does oxygen form?
2
Most of the time non-metals ……. RIG
gain electrons so are reduced.
Two gasses given off when heating ammonia chloride?
ammonia, hydrogen chloride
Solid made when ammonia chloride is heated?
ammonia chloride
What processes occur when ammonia chloride is heated?
decomposition and neutralization
color of lead?
silver
metal hydroxide + metal sulfate ->
metal hydroxide + sodium sulfate
test for carbonate ions?
HCL
Fizzing.
test for sulfate ions?
Barium chloride
You will see a white precipitate.
Test for ammonia ions?
- add NaOH and warm
- test gas
- litmus paper should turn blue
Example structural formula of propane?
CH3 CH2 CH3
solid and gas products formed during in complete combustion?
Carbon
carbon monoxide
condition needed for hydrogen bromide reaction?
UV light
Organic product from hydrogen bromide reaction?
bromomethene
Equation for reaction between methane and bromine?
C3H8 + 5O2 -> 3CO2 + 4H2O
Strength of metals depend on the strength of electrostatic forces of attraction between two types of particles?
Elections
Cations
breaking bonds…….
absorbs energy
making bonds…….
releases energy
when a reaction is exothermic….
more energy is released than is absorbed.
equation for anhydrous copper(II) sulfate test with water?
CuSO4 + 5H2O -> CuSO4.5H2O
Suggest why universal indicator is more suitable than methyl orange.
shows if the substance is weakly or strongly acidic, uses more then one color.
Suggest two substances that can be used to compare the re-activity.
Water
Oxygen
Industrial uses of hydrogen?
Ammonia and HCL
Process in which particles more through a tube in experiment to make chlorides?
Diffusion.
Color of Bromine water test?
Orange/Yellow
to colourless
Dibromethane.
4 hydrogens, 2 Bromine, 2 Carbon
Use of Aluminium?
aircraft material.
LOW DENSITY
Two observations of all Group 1 metals?
Fizz, turn into a ball
Group one metals turn UI….
Blue, Alkali solution OH- ions
ionic bonding question 3 marks?
Electrons being transferred between oxygen and sodium.
idea of sodium losing.
Correct number of electrons involved.
Bromides are
acidic
Chlorides are
alkali
if solution is acidic..
H+ ions formed
If solution is alkali…
OH- ions formed
Hydrogen chloride gas dissociates in water……
but not in Methylbenzene
When hydrogen chloride dissolves in water…..
molecules split up into H+ ions and Cl- ions, this is dissociation.
When hydrogen chloride dissolves in methylbenzene..
it does not dissociate
LITMUS PAPER BLUE!!!
What happens during neutralization reactions?
Acid contains Hydrogen ions
A base contains hydroxide ions
They neutralize and the products are neutral
neutralization reaction?
acid + base -> salt + water.
Example of base?
- copper oxide
- zinc hydroxide.
Bases that are also soluble in water are called
Alkalis
Example of Alkalis?
- sodium hydroxide
- potassium hydroxide
All alkalis are
bases
compounds with .H2O are….
hydrated
two metals that can be reacted with water to safely produce hydrogen?
iron
magnesium
Solid used in the extraction of both iron and aluminium?
carbon
gas that is needed to the extraction of iron? why?
oxygen - to combust and produce heat
formula name and quickname of: Calcium oxide and calcium silicate?
CaO - quicklime
CaSiO3 - Slag
Properties of limestone that need to be kept the same when retesting?
- Surface area
- Mass
Why universal indicator may not be good in a experiment?
Color change is gradual, not sharp or defined.
Alternatives litmus paper or methyl orange.
increasing pressure on a equilibrium reaction?
shifts to the side with fewest gas molecules.
why is aluminium a good conductor?
delocalised electrons.
they are able to move between atoms are flow.
Two ways of collecting gas?
- test tube, downward displacement of water.
- gas syringe.
Colour of Mg and MgO?
Gray silver
white
Phenolphthalein?
colourless -> pink
H2SO4
test for carbonate?
add named acid.
- test for CO2
hydrogen chloride dissolved in water?
UI goes red
H+ ions
hydrogen chloride dissolved in methylbenzene?
No color change.
No h+ ions formed.
How does sacrificial protection work (2)
metal more reactive then other
metal reacts in preference to other.
How can u find positive of metal x nitrate in re activity series?
- make solution of x nitrate
- add metal
- if reaction occurs metal is more reactive then x
- Work down the re-activity series till reaction occurs.
What is the type of reaction that occurs with the rusting of iron?
oxidation
Chemical test for chloride ions?
Silver nitrate solution.
Nitric acid.
White precipitate.
HCL + Mg
MgCl2 + Cl2
Exothermic reaction, increase the temperature?
Increase the rate of reaction.
Kinetic theory
which side has the fewest gas molecules?
N2 + 3H2 = 2NH3
right, discount ratio!!!
Ammonium nitrate
(NH4)(NO3)
why is it difficult to get a an accurate formula for air?
Mixture of different gasses
Advantage of using helium over hydrogen?
non-flammable
Properties of Aluminium?
Malleable
Low density
what type of reaction is the bromine water test?
Addition reaction
a substance that can be added to lower PH?
Any acid.
why has excess of substance X been used?
to displace all of other element.
what colour does bromine turn most things?
Brown
Carbonates are normally in …………. form?
solid
Explain graphs points to include?
Trend
Linear, non-linear
Proportional?
Why must litmus paper be damp before use?
water needed to form OH- or H+ ions
suggest why the actual yield of ammonia is lower than the expected yield?
equilibrium not reached.
Two features of a dynamic equilibrium?
- rate of forward reaction = rate of reverse reaction
- forwards and backwards reactions still occurring.
How is ammonia separated from un-reacted hydrogen and nitrogen?
- mixture of gasses cooled.
- ammonia condenses.
Burning alcohols: explain why students results are lower then data book entry’s?
- Lost heat to surroundings
- Flame is moved around by draughts.
How is energy given out during a reaction?
- Braking bonds is endothermic/ takes in heat energy.
- Making bonds is exothermic gives out energy
- MORE HEAT ENERGY GIVEN OUT THEN TAKEN IN.
How does carbon dioxide cause cloudlessness in limewater?
caused by formation of white precipitate
What apparatus be used to collect dry oxygen gas
gas syringe
Explain how carbon dioxide is effective in fire extinguishers
blankets the fuel.
prevents oxygen from reaching the fuel .
testing for ammonium ions, why nitric acid?
to remove carbonate ions
white precipitate with silver nitrate?
silver chloride
what fuel is formed when C2H6 is cracked to make C2H4?
H2 hydrogen
What is meant by the term bio degrade?
polymer breaks down, decomposes
by bacteria or microbes
property that prevents addition polymers from easily bio degrading?
inert or unreactive
Calculate relative atomic mass of isotope
1) mass 85 72%
2) mass 87 28%
(85 x 0.72) + (87 x 0.28) =
colour when H2SO4 neutralizes the 2NaOH?
pink to colourless
