Conditions & Reagents

Question 1

Conditions for catalytic cracking of alkanes (Alkanes -> Alkenes)

Answer 1

600 degrees celcius, Al2O3/SiO2 catalyst

Question 2

Conditions for substitution of Alkane (Alkane -> Halogenoalkane)

Answer 2

Presence of UV Light

Question 3

Conditions for addition of halogen to alkenes (alkene -> halogenoalkane)

Answer 3

Addition of Cl2/Br2 dissolved in CCl4

Question 4

Lab conditions for addition of steam to alkenes (alkanes -> alcohol)

Answer 4

1. Concentrated H2SO4 reagent at room temp
2. Add H2O and warm

Question 5

Conditions for addition of hydrogen to alkenes (alkene -> alkane)

Answer 5

Platnium Catalyst

Question 6

Conditions for fermentation of glucose (glucose -> ethanol)

Answer 6

1. Presence of Yeast
2. Less than or equal 37 degrees celcius
3. Absence of air

Question 7

Conditions for elimination of alcohols (alcohol -> alkene)

Answer 7

Excess concentrated H2SO4, 170°C

Question 8

Conditions for oxidation of primary/secondary alcohols (alcohol -> acid/ketone)

Answer 8

1. Aqeuous H2SO4
2. KMnO4 or K2Cr2O7
3. Heat

Question 9

Conditions for condensation of alcohol (acid+alcohol -> ester)

Answer 9

1. Reflux heating
2. Concentrated H2SO4 catalyst

Question 10

Test to differentiate alkane and alkene

Answer 10

Addition of bromine dissolved in CCl4 to seperate samples of alkene and alkane in the dark

Observation: Orange-red bromine solution is decolourised in test tube with alkene

Question 11

Test to differentiate between primary/secondary alcohol and tertiary alcohol (Acidified KMnO4)

Answer 11

Add acidified KMnO4 to seperate test tubes containing primary/secondary and tertiary alcohols

Observation:
Primary/secondary: Colour of acidified KmNO4 changes from purple to colourless

Tertiary: No colour change observed

Question 12

Test to differentiate between primary and secondary alcohol

Answer 12

1. Oxidise with acidified KMnO4
2. Add Mg or CaCO3.
3. The sample with effervescence observed is primary alcohol

Question 13

Test for oxidising agents

Answer 13

Add aqueous KI to test for presence of oxidising agent
1. KI is oxidised to I2
2. Changes from colourless to brown

Question 14

Test for reducing agent (Acidified Potassium manganate VII)

Answer 14

Add acidified potassium manganate VII or K MnO4 to test for reducing agent
1. MnO4 is reduced to Mn2+
2. Solution colour changes from purple to colourless

Question 15

Test for reducing agent (Acidified potassium dichromate VI)

Answer 15

Add acidified potassium dichromate (VI) or K2Cr2O7to test for reducing agent
1. Cr2O7 2- is reduced to Cr3+
2. Solution colour changes from orange to green

Question 16

Conditions for Habers Process

Answer 16

1. Pressure of 250 atm
2. Temperature of 450°C
3. Fe (s) (finely divided iron) as catalyst

Question 17

Standard electrode potential conditions

Answer 17

1. Temperature at 298K or 25°C
2. Gas pressures at 1bar
3. Aqeuous ions at concentration of 1moldm-3