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141 Cards in this Set
- Front
- Back
COLOUR OF COPPER (II) CRYSTALS: |
blue |
|
COLOUR OF IRON II CRYSTALS: |
pale green |
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COLOUR OF CHROMIUM III CRYSTALS: |
GREEN! |
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COLOUR OF NICKEL II CRYSTALS: |
GREEN. |
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COLOUR OF MANGANATE II CRYSTALS/SOLUTION: |
PURPLE! |
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COLOUR OF IRON III CRYSTALS: |
BROWN! (looks like dirt really...) |
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COLOUR OF MANGANESE (II) CRYSTALS: |
pink |
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COLOUR OF CHROMATE (VI) CRYSTALS: |
YELLOW!! |
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COLOUR OF DICHROMATE (VI) |
ORANGE. |
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COLOUR OF ZINC (II) |
COLOURLESS (how boring) |
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COLOUR OF SODIUM FLAME: |
YELLOW |
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COLOUR OF POTASSIUM FLAME: |
LILAC
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COLOUR OF CALCIUM FLAME: |
Yellow-RED (like bricks) |
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COLOUR OF LITHIUM FLAME: |
RED |
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COLOUR OF STRONTIUM FLAME: |
CRIMSON RED |
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COLOUR OF BARIUM FLAME: |
PALE GREEN |
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TEST FOR OXYGEN: |
RELIGHTS SPLINT |
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TEST FOR CO2: |
TURNS LIMEWATER CLOUDY |
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TEST FOR AMMONIA |
Turns red moist litmus paper blue |
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TEST FOR NITROGEN DIOXIDE |
BROWN GAS (insoluble) |
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TEST FOR HYDROGEN: |
IGNITES WITH POP |
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TEST FOR HYDROGEN CHLORIDE GAS: |
steamy fumes when exposed to moist air |
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TEST FOR CHLORINE |
PALE GREEN GAS |
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TEST FOR BROMINE |
BROWN GAS (soluble in organic solvents) |
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TEST FOR IODINE GAS |
PURPLE GAS |
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TEST FOR WATER VAPOUR: |
TURNS BLUE COBALT CHLORIDE PAPER PINK. |
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Source of:
Carbon Dioxide emitted with acid |
Carbonates |
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Source of: Hydrogen evolved with acid |
Metals |
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In acids, yellow solution turning orange |
Chromate (VI) to Dichromate (VI) |
|
in acids: Sulfur dioxide evolved and pale yellow precipitate formed |
thiosulfate |
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How do you test for a reducing agent? |
1) it decolourises potassium manganate (VII)
2) turns acidified dichromate (VI) from orange to green |
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Name 3 very effective reducing agents: |
1)iron(II) ions 3)hydrogen peroxide. |
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How to test for oxidizing agents: |
1)it liberates iodine as a brown solution or black solid in aqueous potassium iodide
2)Iodine gives blue/black colour with starch. |
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Give 6 examples of excellent oxidizing agents: |
1)acidified manganate(VII) ions 2)acidified dichromate(VI) ions 3)hydrogen peroxide 4)copper(II)ions 5)aqueous chlorine 6)aqueous bromine. |
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Manganate (VII) and hydrogen peroxide (H202)? |
Brown Precipitate |
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Chromium iii + NH3 gives what colour precipitate and is it soluble or insoluble? |
green precipitate. soluble |
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manganese ii + NH3 gives what colour precipitate and is it soluble or insoluble? |
offwhite precipitate insoluble |
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iron ii + NH3 gives what colour precipitate and is it soluble or insoluble? |
green precipitate which turns brown insoluble |
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iron iii+ NH3 gives what colour precipitate and is it soluble or insoluble? |
brown precipitate insoluble |
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nickel ii + NH3 gives what colour precipitate and is it soluble or insoluble? |
green precipitate soluble ---> forms blue solution |
|
copper ii + NH3 gives what colour precipitate and is it soluble or insoluble? |
blue precipitate soluble ----> blue solution
|
|
zinc ii+ NH3 gives what colour precipitate and is it soluble or insoluble? |
white precipitate soluble ----> colourless solution |
|
magnesium + NH3 gives what colour precipitate and is it soluble or insoluble? |
white precipitate insoluble |
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What occurs when SO4 (sulfate) is added to BaCl (and HCl to remove traces)? |
forms white insoluble precipitate |
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What occurs when SO3 (sulfite) is added to BaCl (and HCl to remove traces)? |
forms white soluble precipitate |
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What occurs when BaCO2 is added to BaCL (and HCl to remove traces)? |
precipitate dissolves with effervescence |
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What could you use to test for Sulfate ions (SO4-)? |
BaCl solution (white precipitate formed) |
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What would you use to test for Halide ions? |
Use aqueous silver nitrate. after adding nitric acid to remove any other impurities! |
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What colour is the chloride anion once tested for halide ions after being added to aqueous silver nitrate? Is it soluble? |
white. Yes, it is soluble |
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What colour is the Bromide anion once tested for halide ions after being added to aqueous silver nitrate? is it soluble? |
cream. Yes, soluble in excess |
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What colour is the Iodide anion once tested for halide ions after being added to aqueous silver nitrate? is it soluble? |
yellow. No, insoluble |
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Using sulfuric acid to test for anions in Chloride, what should we see? |
steamy fumes, vigorous reaction |
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Using sulfuric acid to test for anions in Bromide, what should we see? |
steamy fumes, brown vapour, vigorous reaction |
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Using sulfuric acid to test for anions in Iodide, what should we see? |
steamy fumes, black solid, purple vapour, yellow solid, vigorous reaction |
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If an organic compound dissolves in water what is it likely to be? |
- Amines -carboxylic acids -phenols |
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How would you test for alkenes? |
shake with orange bromine water, yellow solution is decolourised. |
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How would you test for primary/secondary alcohols, aldehydes? |
warm with acidified potassium dichromate(VI) turns orange-----> green |
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How would you test for phenols? |
shake with orange bromine water. white precipitate is formed. |
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How would you test for halogenoalkanes with Cl, Br and I anions? |
warm with aqueous sodium/potassium hydroxide, acidify with dilute nitric acid then add aqueous silver nitrate
precipitates: Cl- white Br- cream I- yellow |
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How would you test for the OH group in alcohols and carboxylic acids? |
phosphorus(V) chloride
steamy fumes of HCl that turn damp blue litmus paper red |
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How to test for C=O groups in aldehydes and ketones? |
use 2,4−dinitrophenylhydrazine solution -orange precipitate |
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More tests for aldehydes? |
-boil with Benedict's solution ---> blue to red! -warm with Tollen's agent ---> forms silver mirror!
|
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How to test for carboxylic acids? |
add sodium or potassium carbonate or hydrogencarbonate solution ----> effervescence |
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Test for alcohols? |
warm with carboxylic acid and a few drops of concentrated sulfuric acid
-----> gives ester-smell like glue |
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Test for aromatic amine? |
sodium nitrite and dilute hydrochloric acid followed by an alkaline solution of phenol in ice-cold conditions -----> orange precipitate. |
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Test for methyl ketone or athanal? |
iodine in alkaline solution ----> pale yellow precipitate. |
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Simple way for testing for alcohol, phenol or carboxylic acid |
add a small piece of sodium ----> effervescence. |
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How do you carry out a flame test?
|
1) first, the chromium of platinum wire is dipped in to HCL so it becomes a chloride salt. Chloride salts are the most volatile so they turn into gas as soon as they enter the flame.
2) make sure the flame is colorless. 3) observe colour. |
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Why do flames turn different colors when they detect a specific cation?
|
the heat energy of the flame causes the compound to vaporize so that an electron in the metal jumps up to a higher energy level. When the electron falls back down an energy level, energy is released in the form of light in different wavelengths which are different colors.
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Source of Carbon Dioxide from solids:
|
metal carbonates
|
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Source of Oxygen from solids:
|
group 1 nitrates
|
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source of oxygen + nitrogen dioxide from solids:
|
group 2 nitrates
|
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source of water from solids:
|
hydrated solids or hydrogen carbonate
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A white solid sublimes on the cooler part of the tube ?
|
ammonium salt is present
|
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How to test for sulfur dioxide:
|
it is a colorless gas which is acidic and decolourises acidified potassium dichromate paper/solution from green to orange.
|
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Source of sulfur dioxide?
|
-warming an acid with sulfite.
-burning sulfur -reducing concentrated sulfuric acid. |
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Test for nitrogen dioxide:
|
brown gas
|
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Test for chlorine with litmus paper?
|
turns moist red litmus paper blue then bleaches it white.
|
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Test for Bromine:
|
pass through a solution of excess potassium iodide and the colorless solution becomes deep red brown because the iodide is liberated and then reacts with excess I- ions. Excess iodide would give a grey black precipitate thats black.
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Effervescence of a colorless, odorless gas which gives a white precipitate with limewater.
|
carbonate or hydrogen carbonate
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sulfur dioxide evolved on warming and decolourises acidified potassium dichromate (vi) paper to green (from orange)
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sulfite
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Test for reducing agents:
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decolourises aqueous acidified potassium manganate (vii) form purple to colourless OR turns acidified potassium manganate from orange to green.
|
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What are some really good reducing agents?
|
- iron (ii) ions
- iodide ions -hydrogen peroxide -sulphite ions |
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Add hydrogen peroxide, and get a brown precipitate?
|
MNO2
|
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Add hydrogen peroxide, and purple solution decolourises
|
mangante (vii) in acid
|
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Add hydrogen peroxide and pale green solution turns yellow
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iron ii to iron iii in acid.
|
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What are the soluble ionic compounds?
|
- group 1 salts
-ammonium salts -all nitrates -all chlorides except silver and lead - all sulfates except barium, strontium, lead. |
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Which are insoluble compounds?
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all carbonates apart from group 1 carbonates and ammonium carbonates.
all hydroxides apart from group1 hydroxides, barium hydroxide and ammonium hydroxide. |
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Test for group 1 hydrogencarbonates:
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-drops of water condense on upper part of tube when heated.
-Gas produced also makes limewater milky. |
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Test for sodium/ potassium nitrates:
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Under heat:
-melts and gives off bubbles of a colorless gas which relights a glowing splint |
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Test for lithium or a group 2 nitrate under heat:
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Under heat:
-melts and gives off brown gas and a gas that is colorless and relights splint. |
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Test for group 2 carbonates or lithium carbonate under heat:
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Under heat:
-no water produced like hydrogen carbonates but gas evolved turns lime water milky |
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Test for ammonium chloride under heat:
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-solid sublimes in upper part of test tube
|
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What are the products formed in a thermal decomposition of a group 1 nitrate?
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- a NO2 (a nitrogen dioxide)
-O2 (oxygen) e.g: 2KNO3 ------> 2KNO2 + O2 |
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What are the products formed in a thermal decomposition of a group 2 nitrate?
|
-an oxide
-a nitrogen dioxide -Oxygen e.g: 2Mg(NO3)2 ------> 2MgO + 4NO2 + O2 |
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Test for carbonates, hydrogen carbonates with acid:
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-effervescence (bubbles)
-limewater goes milky |
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How do you distinguish a carbonate from a hydrogen carbonate?
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If it is a hydrogen carbonate:
test with boiling water and there should be effervescence and gas evolved that turns limewater milky. OR -make a solution with the unknown carbonate and add calcium chloride solution. There should be a white precipitate IF there is a carbonate and no precipitate if it is a hydrogen carbonate. |
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How to test for ammonium salts not under heat:
|
-add to sodium hydroxide and test gas with either damp litmus paper.
OR a glass rod dipped into concentrated HCL. Results: -gas turns red litmus paper blue and blue litmus paper stays blue (ammonia formed) -white smoke (ammonium chloride) |
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Test for inorganic chloride:
|
-add concentrated sulfuric acid and test gas formed with 1) glass rod dipped in ammonia or 2) damp litmus paper.
results: 1)bubbles, steamy fumes (hydrogenchloride) 2)white smoke, red litmus paper stays red blue turns red. test this in a fume cupboard |
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Test for inorganic Bromide:
|
Add sulfuric acid
results: steamy fumes (hydrogen bromide), red-brown gas (bromine) |
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Test for inorganic Iodide:
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Add sulfuric acid
results: steamy fumes (hydrogen iodide), purple vapour (iodine), yellow solid (sulfur), bad smelling egg-smell (H2S) |
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More tests for the chloride, bromide and iodide halides:
|
-Add dilute nitric acid to the solution of the unknown and then silver nitrate.
finally, test solubility of precipitate with first dilute, then concentrated ammonia results: -chloride (white precipitate turning purple) soluble in dilute ammonia -Bromide (cream precipitate) insoluble in dilute but soluble in concentrated ammonia -Iodide (yellow precipitate) insoluble in concentrated ammonia |
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What is the ionic equation for the precipitation of a silver halide?
|
Ag+ (aq) + X- (aq) -----> AgX (s)
'X' is the halide |
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How to test for the bromide or iodide halides without using alkali:
|
using chlorine water and then add starch solution
results: -brown or yellow solution formed (bromine or iodine formed) - test with starch should turn blue-black IF it is an Iodide but not bromide. |
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Test for sulfates:
|
add HCL then barium chloride
-white precipitate formed |
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Test for nitrates without heating:
|
-Add Devarda's alloy (aluminum powder)
and dilute sodium hydroxide and warm with dilute sodium hydroxide then test the gas using a rod dipped into HCL (white smoke) or litmus paper turns blue. |
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How to test for hydroxides and which hydroxides are soluble and which are not?
|
Add sodium hydroxide: calcium ----> slight white precipitate magnesium --->white precipitate soluble:-group 1 hydroxides -calcium hydroxide slightly soluble insoluble: -magnesium hydroxides. |
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How to test for an acid:
|
-add zinc or magnesium and test the gas that is evolved.
there should be effervescence and gas ignites with squeaky pop. |
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Sherlock's corner:
"it burns with a clean, non smoky flame" when heated (what sort of hydrocarbon is it)? |
low carbon to hydrogen ratio so could be an alcohol
|
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Sherlock's corner:
"it burns with a smoky flame" when heated |
high carbon to hydrogen ratio so could be cyclic alkene or alkane
|
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Testing for hydrocarbons?
|
-add to water. Two layers form so it is a hydrocarbon
-dissolves then it is an alcohol ( it hydrogen bonds with water) |
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Testing for the c=c bond to find if something is an alkene?
|
-Add orange bromine water and shake:
the orange bromine water decolourises and two layers form. -Add sulfuric acid then potassium manganate (vii) and shake. ---> purple solution becomes colorless and two layers form |
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Test for the OH group:
|
-add a small piece of sodium and there should be effervescence, sodium disappears or a white solid forms.
or -add phosphorus (v) chloride and test for gas using rod dipped in ammonia ---> steamy fumes, white smoke |
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What experiment would we use to differentiate between a primary, secondary and tertiary alcohol?
|
Add sulfuric acid and aqueous potassium dichromate (vi) then warms in beaker with hot water.
Orange solution turns green (primary or sec) solution stays orange (tertiary) |
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Whats one way we can test for a halogenoalkane using ethanol?
|
add concentrated sodium hydroxide in ethanol and fit the test tube with a delivery tube and warm gently passing any gas evolved in orange bromine water which should become colorless in the presence of one.
|
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Sherlock's corner:
this halogenoalkane precipitate completely dissolves in ammonia |
it is a chloroalkane!
|
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Sherlock's corner:this halogenoalkane precipitate only dissolves in concentrated ammonia
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is is a bromoalkane
|
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Sherlock's corner:this halogenoalkane precipitate does not dissolve in ammonia
|
is is an iodoalkane
|
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Are halogenoalkanes soluble in water?
|
NO! two layers form.
|
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How does the OH bond appear on the IR spectra?
|
its looks very broad
|
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What is the absorption frequency of the C-H bond?
|
3000-3853
|
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What is the absorption frequency of the c=c bond?
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1669-1645
|
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What is the absorption frequency of the OH bond?
|
a broad beak at 3750-3200
|
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When carrying out a titration experiment, how can we avoid any errors?
|
-weighing: weigh to 0.01g
-measure all titre volumes to 0.05 cm3 -pipette: wash out with solution before use and ensure that their are no bubbles in the stem of the pipette when used. -burette:washed with solution and filled just above 0 mark. -recording: read at the bottom of the meniscus -consistency: repeat titrations so that we get at least two that are concordant which can be added and divided by two to get the average titre. |
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What is a titre?
|
the difference between the first and initial readings in a titration
|
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Describe how iodine/thiosulfate titrations are carried out:
|
-weigh solid oxidising agent and dissolve in water to make 250cm3 (or use aqueous hydrogen peroxide as the oxidizing agent). 25cm3 portions of the oxidizing agent solution are pipetted into a conical flask and some sulfuric acid is added. Excess potassium iodide is also added which reacts with the oxidizing agent to liberate iodine which is then titrated against a solution of sodium thiosulfate until it fades to a pale yellow colour. Starch is then added drop by drop until the blue black colour disappears (no more starch).
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What is the formula for heat change in enthalpy change experiments?
|
mass of solution x specific heat capacity (4.18 for water) x enthalpy change
|
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How would you conduct an enthalpy change experiment?
|
1)mix measured amounts and stir with thermometer in the polystyrene cup in the glass cup then measure the initial and final temp (for rapid reactions like acid/base or acid/carbonate.
2)record the initial temp of one solution then begin adding the other solution at regular intervals measuring the temp and plotting a graph of temp against volume |
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What are some technical errors that could occur during an enthalpy change experiment?
|
-not using the bottom of the meniscus to read to volumes.
-failing to stir the mixture thoroughly so not observing correct temperature. -not adding the solid (such as a carbonate) in small portions carefully so when gas is produced, liquid spills out and foams. |
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What are some recording errors that could occur during an enthalpy change experiment?
|
-failing to record masses to 0.01g
-failing to record the temperature to 0.1 (always on decimal place) -failing to record time correctly per minute |
|
How would you measure the percentage error of a thermometer?
|
error for each reading is + or - 0.1 for a thermometer so we would use this formula:
0.1 _________ x 100% ΔT
|
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Would increasing the volume of a solution increase/decrease the percentage error of a thermometer? Why?
|
increasing the volume of the liquid will increase the heat, but so would the mass so it is proportional and the ΔT won't be affected. BUT if you increase the concentration then the ΔT will be affected meanwhile the mass won't change so more heat would be produced making it more accurate.
|
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How do we prepare a simple salt?
|
1)the solid reactant is added to the acid which has been gently heated
2) the mixed solution is now filtered through a funnel and poured into an evaporating basin (dish) and heated until only half of the filtrate remains 3) leave overnight to cool and form crystals and blot dry with filter paper and weigh |
|
What technical errors could we face when conducting an experiment to prepare a simple salt?
|
-acid solution is not hot enough (to dissolve solid).
-adding solid too fast that the solid causes the liquid to froth and overflow -evaporating too little/too much of the solution. |
|
When forming a salt, later onwards, how would we measure the crystals?
|
- measure to 2 decimal places
-describe salt's colour and shape (diamond) |
|
How would you prepare the double-salt Ammonium Iron (ii) sulfate?
|
1)some iron fillings are placed with an excess of hot sulphuric acid meanwhile any unreacted iron is filtered off.
2)Dilute ammonia is added in portions to another beaker with dilute sulfuric acid until the solution becomes alkaline and turns litmus paper blue. The excess ammonia is boiled off. 3) the two solutions are mixed together in a beaker and heated until half the volume and is then left to cool |
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How will you prepare the experiment for the oxidation of a primary alcohol to form an aldehyde? |
1) an alcohol is dissolved in a solution of potassium dichromate (vi) slowly and sulfuric acid which is then connected to the distillation apparatus and heated using the bunsen burner. 2) when it cools down from the water passing through the condenser, it cools down and enters a separate beaker as an aldehyde. |
|
What is the equation for the oxidation of ethanol: |
CH3CH2OH + (O) ---------> CH3CHO + H20 |
|
How will you prepare the experiment for the oxidation of a primary alcohol to form a carboxylic acid? |
use same procedure to form primary alcohol but do not use distillation apparatus but heat under reflux until solution becomes green (from orange) due to the presence of the chromium iii ions from the acidified dichromate and becomes a ketone from the aldehyde. |
|
How do you distinguish between aldehydes and ketones? |
add 2,4 dinitrophenylhydrazine to produce and orange precipitate. -then add tollens reagent: should form a silver mirror in the presence of an aldehyde but no change in the presence of a ketone. or add Benedict's solution: gives red precipitate from blue in the presence of an aldehyde but stays blue with ketones. |
|
How do you dehydrate an alcohol? Use an example. |
add an alcohol such as cyclohexanol to concentrated phosphoric acid which becomes a cyclohexene that is distilled. This can be tested using orange bromine water which decolourises. |