|
Hint
|
|
Answer
|
|
1. ____ the balance
|
|
zero
|
|
2. place a ____ ____ on the balance
|
|
weighing bottle
|
|
3. accurately record the mass of the ____ plus the weighing bottle
|
|
solid
|
|
4. empty the solid into the ____ and accurately reweigh the empty weighing bottle
|
|
glassware
|
|
5. ____ mass of empty weighing bottle from mass of solid + weighing bottle
|
|
subtract
|
|
1. rinse pipette with ____ ____ and then a small volume of the solution to be pipetted
|
|
distilled water
|
|
2. using a ____ ____ draw enough liquid into the pipette until it is exactly the right volume
|
|
pipette filler
|
|
you will know it's the right volume when the ____ __ __ ____ is level with the mark
|
|
bottom of the meniscus
|
|
3. ____ the outside of the pipette
|
|
dry
|
|
4. run the liquid from the pipette to the ____
|
|
glassware
|
|
5. touch the tip of the pipette to the ____ of the glassware
|
|
inside
|
|
1. rinse burette with ____ ____ and then a small volume of the solution to be used
|
|
distilled water
|
|
2. close the ____ ____
|
|
burette tap
|
|
3. pour the solution into the burette using a ____. fill to above the zero line
|
|
funnel
|
|
4. use a ____ to hold your burette in place
|
|
clamp
|
|
5. open the tap and allow the solution to run into a beaker until there are no ____ ____
|
|
air bubbles
|
|
6. record the start reading to the nearest ____ cm^3
|
|
0.05
|
|
7. carry out the titration and record the end reading to the nearest ____ cm^3
|
|
0.05
|
|
8. find the ____ by subtracting the initial reading from the final reading
|
|
titre
|
|
1. use an ____ ____ to collect the gas over water
|
|
inverted burette
|
|
the system must be ____ ____
|
|
gas tight
|
|
2. the ____ ____ delivers gas to the burette
|
|
delivery tube
|
|
3. the burette is inverted in a ____ ____ and itself filled with water initially
|
|
water trough
|
|
4. the ____ will enter the burette and you can take a reading
|
|
gas
|
|
1. put the reactants in a ____ ____ flask
|
|
pear-shaped/round-bottomed
|
|
2. add ____ ____ ____ (stop large bubbles forming suddenly and allow for a smooth boiling process)
|
|
anti bumping granules
|
|
3. vertically attach a ____ so the water flows in at the bottom and out at the top
|
|
condenser
|
|
4. heat with a ____ ____ so the reaction mixture boils gently
|
|
heating mantle
|
|
5. vapours should reach no more than ____ up the column before condensing back into a liquid
|
|
halfway
|
|
1. mix the organic product with another ____ liquid such as water
|
|
immiscible
|
|
2. allow the layers to separate and dispose of the aqueous layer using a ____ ____
|
|
separating funnel
|
|
3. if acid impurities are present, add ____ ____ ____ solution and shake well to remove them
|
|
sodium hydrogen carbonate
|
|
4. if the crude product is alkaline and needs neutralising, add a ____ ____ until it's neutral
|
|
dilute acid
|
|
5. dry the crude product by adding ____ ____ ____ and swirling
|
|
anhydrous sodium sulfate
|
|
6. the pure product can then be separated by ____
|
|
distillation
|
|
1. carry out an ____ ____ ____ to find how much acid solution is needed to neutralise 25cm^3 alkaline solution
|
|
acid base titration
|
|
2. transfer 25cm^3 alkaline solution to a clean ____ ____
|
|
conical flask
|
|
3. use a ____ to add the correct amount of acid to neutralise the alkali
|
|
burette
|
|
4. transfer the neutralised solution to a clean ____ ____
|
|
evaporating basin
|
|
5. heat over a Bunsen burner to evaporate the water until ____ start to appear
|
|
crystals
|
|
6. filter the mixture and wash the residue with cold ____ ____
|
|
distilled water
|
|
7. transfer the residue to a ____ ____ and heat in an oven to dry the solid
|
|
watch glass
|
|
8. the oven's temperature should be below the melting point of the ____
|
|
salt
|
|
9. at regular intervals, remove the watch glass and solid, cool in a ____ and weigh
|
|
dessicator
|
|
10. heat until the solid has dried to a ____ ____
|
|
constant mass
|
|
11. leave to cool in a ____ (these allow materials to cool in a dry atmosphere so prevent reabsorption of moisture)
|
|
dessicator
|
|
1. in a beaker, warm ____ insoluble base in dilute acid
|
|
excess
|
|
2. warm until the solution is ____, adding more solid base if needed
|
|
neutral
|
|
3. leave to ____
|
|
cool
|
|
4. filter off excess solid base and transfer the ____ to a clean, dry evaporating basin
|
|
filtrate
|
|
5. follow the procedure for ____ (given above)
|
|
crystallisation
|
|
1. add in equal volumes of the desired salt solutions in a beaker to form a ____ of the insoluble salt
|
|
precipitate
|
|
2. filter and wash the precipitate several times with cold, ____ ____
|
|
deionised water
|
|
3. transfer the precipitate to a clean watch glass and place in a ____ ____
|
|
drying oven
|
|
ensure the oven's temperature is ____ the melting point of the salt
|
|
below
|
|
4. heat to constant mass and then leave to cool in a ____
|
|
dessicator
|
|
1. put the mixture in a pear-shaped flask and add ____ ____ ____
|
|
anti bumping granules
|
|
2. the thermometer should read the temperature of the ____
|
|
vapour
|
|
3. when the vapour temperature is about ____ degrees below the boiling point of the liquid, put the collecting beaker in place
|
|
2/two
|
|
4. collect the liquid until the temperature of the vapour rises ____ the boiling point of the liquid you are collecting
|
|
above
|
|
you can repeat this for multiple ____ in a mixture if necessary
|
|
liquids/substances
|
|
1. spot the test mixture and ____ ____ on a pencil baseline 1cm from the base of the TLC plate
|
|
reference samples
|
|
2. suspend the plate in a baker containing the ____
|
|
solvent
|
|
3. cover with a watch glass to prevent ____
|
|
evaporation
|
|
4. remove the plate when the solvent is near the top and mark the ____ ____ with a pencil
|
|
solvent front
|
|
5. allow the plate to ____
|
|
dry
|
|
6. locate spots. you may need to add a stain or view under ____ ____
|
|
ultraviolet light
|
|
____ is used to detect colourless organic compounds
|
|
iodine
|
|
____ is used to detect compounds with free amino groups such as proteins, amino acids, and amines
|
|
ninhydrin
|
|
the TLC plate fluoresces under ____ ____. compounds with aromatic rings or conjugated structures appear as dark spots
|
|
ultraviolet light
|
|
5. match the calculated ____ values with those in a database
|
|
Rf
|
|
1. select a solvent in which the desired substance is very soluble at high ____ and insoluble at low ____
|
|
temperatures
|
|
2. dissolve the mixture in the ____ quantity of hot solvent
|
|
minimum
|
|
3. filter to remove any ____ ____ and retain the filtrate
|
|
insoluble impurities
|
|
for this step, use a ____ ____ to retain heat
|
|
vacuum filtration
|
|
4. leave the filtrate to cool until crystals form and collect the crystals by ____ ____
|
|
vacuum filtration
|
|
5. rinse the crystals with ____ ____
|
|
cold solvent
|
|
6. dry the crystals in a ____ ____
|
|
drying oven
|
|
1. connect a conical flask to a vacuum pump via the ____ ____
|
|
side arm
|
|
2. dampen a piece of filter paper and place flat in the ____ ____
|
|
Buchner funnel
|
|
3. switch the ____ ____ on then pour in the mixture to be filtered
|
|
vacuum pump
|
|
4. this creates a partial ____ so the filtrate is quickly pulled through
|
|
vacuum
|
|
5. disconnect the flask from the vacuum pump before turning the pump off to prevent ____ ____
|
|
suck back
|
|
1. seal the end of a glass ____ ____ by heating it to melting in a Bunsen flame
|
|
capillary tube
|
|
2. tap the ____ end of the tube into a solid so a small amount goes into the tube
|
|
open/unsealed
|
|
3. tap the tube so the solid falls to the bottom of the ____ end
|
|
sealed
|
|
4. fix the tube in melting point apparatus and gently heat the surrounding liquid, ____ to ensure even heating
|
|
stirring
|
|
5. note the temperature at which the solid starts and finishes melting - the difference is the ____ ____
|
|
melting range
|
|
6. compare the ____ value to the published value
|
|
experimental
|
|
the wider the melting range, the more ____ the substance
|
|
impure
|
|
a pure substance melts within ____K of the true melting point
|
|
0.5
|
|
1. calculate the mass of solute required and weigh out in a ____ ____
|
|
weighing bottle
|
|
2. pour 100cm^3 ____ ____ into a 250cm^3 beaker
|
|
deionised water
|
|
3. transfer the weighed ____ into the water
|
|
solute
|
|
4. ____ the weighing bottle to calculate actual mass in the beaker
|
|
reweigh
|
|
5. stir the mixture with a ____ ____ to ensure the solute has completely dissolved
|
|
glass rod
|
|
6. transfer the solution to a clean 250cm^3 ____ ____
|
|
volumetric flask
|
|
7. rinse the beaker and stirring rod with deionised water, ensuring all ____ go into the flask
|
|
washings
|
|
8. add deionised water, swirling at intervals to mix the contents, until the level is within about ____ cm^3 of the mark on the flask's neck
|
|
1
|
|
9. use a dropping pipette to add deionised water so the ____ __ __ ____ is level with the mark on the neck of the flask at eye level
|
|
bottom of the meniscus
|
|
10. insert a stopper in the flask and ____ it several times to ensure thorough mixing
|
|
invert
|
|
1. rinse a clean dry beaker with the ____ ____ then half-fill it
|
|
stock solution
|
|
2. use a pipette filler to pipette 25cm^3 of the stock solution into a 250cm^3 ____ ____
|
|
volumetric flask
|
|
3. make up to the mark with the usual procedure. you will have diluted your solution by a factor of ____ here
|
|
ten
|
|
1. rinse and fill the burette with ____
|
|
acid
|
|
2. pipette 25cm^3 alkaline solution into a ____ ____
|
|
conical flask
|
|
3. add 2-3 drops of ____ and swirl to mix
|
|
indicator
|
|
____ is colourless in acidic solutions and pink in basic ones
|
|
phenolphthalein
|
|
4. run the acid, ____ the flask, until the solution just changes colour
|
|
swirling
|
|
5. the first titration is the ____ titration to indicate roughly how much acid is required
|
|
rough
|
|
6. titrate again. run the acid solution to 1cm^3 below the rough titre then add acid ____
|
|
dropwise
|
|
swirl after each drop until the colour of the ____ just changes
|
|
indicator
|
|
7. repeat until you have three ____ results within 0.10cm^3 of each other and use the mean
|
|
concordant
|
|
____ ions are strong enough oxidising agents to oxidise iodide ions to iodine
|
|
chlorate
|
|
therefore, we can use iodine-thiosulfate titration to find the ____ of a solution of chlorate (I)
|
|
concentration
|
|
1. pour some chlorate (I) solution into a clean, dry beaker and transfer a 25cm^3 ____ into a conical flask
|
|
aliquot
|
|
2. add excess iodide ions, using a measuring cylinder to transfer e.g. 15cm^3 of 0.5 mol dm^3 potassium ____ to the conical flask
|
|
iodide
|
|
3. add excess hydrogen ions by adding 20cm^3 of 1 mol dm^3 ____ ____
|
|
sulfuric acid
|
|
at this stage, the contents will be ____ due to iodine being produced
|
|
brown
|
|
4. fill burette with a standard solution of 0.1mol dm^3 ____ ____
|
|
sodium thiosulfate
|
|
5. put the conical flask on a ____ ____ to make the end point easier to see
|
|
white tile
|
|
6. carry out titrations. near the end point, the contents of the flask will be a ____ ____ colour
|
|
pale straw
|
|
at this point, add a few drops of ____ solution
|
|
starch
|
|
the contents of the flask will turn ____ ____ due to iodine being present
|
|
blue-black
|
|
7. the end point is where the solution is ____
|
|
colourless
|
|
1. select the filter with the ____ colour to the test solution
|
|
complementary
|
|
this allows for the greatest values of ____
|
|
absorbance
|
|
2. make up a range of ____ ____ of the test solution, both above and below the concentration of the unknown solution
|
|
standard solutions
|
|
3. zero the colorimeter using a ____ of pure solvent
|
|
cuvette
|
|
4. measure the ____ of each of the standard solutions
|
|
absorbance
|
|
5. plot a ____ ____ of concentration against absorbance
|
|
calibration curve
|
|
6. measure the absorbance of the ____ sample and use the calibration curve to determine its concentration
|
|
unknown
|
|
1. pour a known volume of water into a copper ____ and record its temperature
|
|
calorimeter
|
|
2. weigh a ____ ____
|
|
spirit burner
|
|
keep the cap on to reduce fuel loss by ____
|
|
evaporation
|
|
3. support the calorimeter over a spirit burner containing the ____ to be tested
|
|
fuel
|
|
4. surround with a ____ ____ to help reduce energy losses
|
|
draught excluder
|
|
5. remove the cap of the spirit burner and light the ____
|
|
wick
|
|
6. carry on heating until the temperature has risen by about ____ to ____ K
|
|
15 20/1520/fifteentwenty/fifteen twenty
|
|
7. ____ the spirit burner and replace the cap
|
|
extinguish
|
|
8. keep stirring the water. make a note of the ____ temperature reached
|
|
highest
|
|
9. weigh the burner again. you can use this to determine ____ ____ __ ____
|
|
enthalpy change of combustion
|
|
1. use a measuring cylinder to add a known volume of a known concentration of acid to an ____ ____
|
|
insulated vessel
|
|
2. use a thermometer to take the initial ____
|
|
temperature
|
|
3. use a ____ ____ to add a known volume of a known concentration of alkali and stir to mix
|
|
measuring cylinder/volumetric pipette
|
|
4. top the vessel with a ____ with a hole in and place the thermometer through the hole in the ____
|
|
lid
|
|
5. record changes in ____ every 30 seconds until there is no further change
|
|
temperature
|
|
6. calculate the maximum temperature reached and use this to determine ____ ____ __ ____
|
|
enthalpy change of neutralisation
|
|
1. add a known volume of a known concentration of reactant solution to an ____ ____
|
|
insulated vessel
|
|
2. add a known mass of solid reactant in ____
|
|
excess
|
|
3. top the vessel with a ____ with a hole in
|
|
lid
|
|
4. record changes in temperature every 30 seconds until there is no ____ ____
|
|
further change
|
|
5. plot a graph of temperature against time and ____ to find the theoretical maximum temperature change
|
|
extrapolate
|
|
1. pass an electric current through the ____
|
|
electrolyte
|
|
you may need to collect ____ products
|
|
gaseous
|
|
if so, do this by filling test tubes with water as these will ____ the water
|
|
displace
|
|
if electrolysis to be carried out to ____ a metal:
|
|
purify
|
|
the ____ will need to be made of the impure metal
|
|
anode
|
|
the electrolyte must contain ____ of that metal
|
|
ions
|
|
the ____ should be made of the pure metal
|
|
cathode
|
|
1. set up apparatus, place several test tubes of water in the ____ ____
|
|
collection trough
|
|
2. strongly heat the ____
|
|
catalyst
|
|
this ensures that when the hydrocarbon vapour passes over it, the temperature is high enough for any ____ reactions to take place
|
|
cracking
|
|
3. heat the ____ gently, collecting any gases that pass into the collection tubes
|
|
hydrocarbon
|
|
4. change and cork any full tubes to prevent ____ ____ and continue to heat
|
|
suck back
|
|
5. discard the first tube of gas because this will just be ____ air
|
|
displaced
|
|
6. continue heating until no more ____ is produced
|
|
gas
|
|
7. remove the ____ ____ from the collection trough before stopping heating to prevent suck back
|
|
delivery tube
|
|
8. leave to ____, then dismantle
|
|
cool
|
|
9. test any liquid product with ____ ____. it should remain orange/brown
|
|
bromine water
|
|
10. test the gas by shaking with bromine water. it should ____
|
|
decolorise
|
|
add a few drops of ____ ____
|
|
bromine water
|
|
if an alkene is present, the bromine water will change from orange/brown to ____
|
|
colourless
|
|
similar to a ____ in that a light source is passed through a sample and absorbance or transmission is measured
|
|
colorimeter
|
|
in the case of a colorimeter, the coloured light used as a source can only be selected from a specific number of different ____
|
|
wavelengths
|
|
a visible spectrophotomer can give data for absorption or transmission for any given value of the ____ ____
|
|
visible spectrum
|
|
1. construct the ____ ____ whose electrode potential is to be measured
|
|
half cell
|
|
for a metal ion/metal half cell, the ____ will be made from the solid metal
|
|
electrode
|
|
if the reaction involves two ions of the same element in different oxidation states, the electron should be ____
|
|
platinum
|
|
in that case, the solution will contain a ____ of the two ions
|
|
mixture
|
|
in all cases, ensure ____ ____
|
|
standard conditions
|
|
2. connect the half-cell to a ____ ____ ____ ____
|
|
standard hydrogen half cell
|
|
3. connect the two electrodes to a ____ ____ ____
|
|
high resistance voltmeter
|
|
ensure the reading on the voltmeter is ____
|
|
positive
|
|
this ensures that the half-cell connected to the ____ ____ of the voltmeter is the positive electrode
|
|
positive terminal
|
|
if the reading is ____ switch the connections on the voltmeter
|
|
negative
|
|
4. take the voltmeter reading to find ____ ____ (or standard ____ ____ in this case
|
|
electrode potential
|
|
you need to ___ the pH electrode for temperature because pH is dependent on temperature
|
|
calibrate
|
|
1. wash the electrode with ____ ____
|
|
deionised water
|
|
2. transfer into a ____ ____ of pH 7.00
|
|
buffer solution
|
|
3. check the bulb of the electrode is completely immersed, then wait for the reading to ____
|
|
stabilise
|
|
ensure the ____ reads 7.00 and adjust to that value if necessary
|
|
meter
|
|
calibrate to pH ___ for acidic solutions
|
|
4.00
|
|
calibrate to pH ___ for alkaline solutions
|
|
10.00
|
|
to measure both acidic and alkaline solutions with a wide range of values, calibrate with acidic, alkaline and neutral ____
|
|
buffers
|
|
first, prepare a ____ ____ in deionised water
|
|
saturated salt
|
|
1. warm deionised water in a small conical flask and add the salt, ____ frequntly
|
|
shaking
|
|
2. keep adding ____ until no more dissolves
|
|
solute
|
|
3. leave the mixture to cool to ____ ____
|
|
room temperature
|
|
4. filter and discard the ____
|
|
residue
|
|
Ksp is ____ dependent, so take the ____ of the solutions you're working with
|
|
temperature
|
|
the second stage is determining ____ of one of the ions in solution
|
|
concentration
|
|
just one is sufficient because the concentration of one ion is ____ to the other
|
|
proportional
|
|
for a basic solution, concentration can be determined using acid-base titration with the ____ ions
|
|
hydroxide
|
|
for a coloured solution, it can be determined by ____
|
|
colorimetry
|
|
1. allow a mixture to reach ____
|
|
equilibrium
|
|
2. determine ____ of one of the components in the equilibrium mixture
|
|
concentration
|
|
3. use this to work out the other concentrations and calculate ____ using the equation
|
|
Kc
|
|
a measure of the closeness of agreement between an individual test result and the accepted reference value
|
|
accuracy
|
|
the closeness of agreement between independent measurements made under the same conditions
|
|
precision
|
|
the difference between an individual measurement and the true value or accepted reference value of the quantity being measured
|
|
error
|
|
an estimate attached to a measurement which characterises the range of values within which the true value is asserted to lie
|
|
uncertainty
|
|
the opposite of uncertainty (if uncertainty is great, the measurement is unreliable)
|
|
reliability
|
|
uncertainty is usually taken to be ____ a division on either side of the smallest scale on the scale you're using
|
|
half
|
|
percentage uncertainty = uncertainty x number of measurements x 100 divided by ____ ____
|
|
measured quantity
|
|
when you use a ____ measuring device, you should record all the figures shown on the instrument
|
|
digital
|
|
when using a non-digital device, you should record all the figures that are certain plus one that is ____
|
|
estimated
|
