Pregunta 1
Pregunta
What catalyst is needed for the addition reaction of hydrogen to an alkene in a lab?
Pregunta 2
Pregunta
The product of this addition reaction is- 2,3-dibromobutane. Thus meaning the addition reaction is [blank_start]bromination[blank_end], This requires [blank_start]room[blank_end] temperature and pressure. A colour change can be seen when this reaction occurs. The solution changes from [blank_start]browny red[blank_end] to [blank_start]colourless[blank_end]. This is commonly known as the test for [blank_start]unsaturation[blank_end].
Respuesta
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bromination
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room
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browny red
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colourless
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unsaturation
Pregunta 3
Pregunta
Tick the answers which are addition reactions for alkenes.
Respuesta
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Bromination
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Hydrobromination
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Hydration
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Oxidation
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Hydrogenation
Pregunta 4
Pregunta
The hydration process in a lab is as follows...
The alkene is [blank_start]heated under reflux[blank_end] then [blank_start]concentrated sulfuric acid[blank_end] is added. Finally [blank_start]water[blank_end] is added, which attaches to the alkene.
Respuesta
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heated under reflux
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heated under high temperature
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heated under low pressure
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concentrated sulfuric acid
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concentrated nitric acid
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concentrated hydrochloric acid
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water
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hydroxide ions
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hydrated salt, such as NaCl.XH2O
Pregunta 5
Pregunta
Hydrobromination's colour change is browny red to colourless.
Pregunta 6
Pregunta
The hydration addition reaction in an alkene in the industry is completed under high temperature and pressure.
Pregunta 7
Pregunta
This specific addition reaction involves a nickel catalyst and high temperature and pressure. Which addition reaction is it?
Respuesta
-
Hydrogenation (Industry)
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Hydrogenation (Lab)
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Hydration (Lab)
-
Hydration (Industry)
Pregunta 8
Pregunta
A heterogenous catalyst (step by step)-
Reactants get [blank_start]adsorbed[blank_end] to surface. Bonds [blank_start]weaken[blank_end] and [blank_start]break[blank_end]. [blank_start]New bonds form[blank_end] between products. Products [blank_start]deadsorb[blank_end] from surfac ([blank_start]diffuse away[blank_end]).
Respuesta
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adsorbed
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weaken
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break
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New bonds form
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Old bonds reform
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deadsorb
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Deabsorb
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diffuse away
Pregunta 9
Pregunta
Catalyst poisons are what to the heterogeneous catalyst surface.
Pregunta 10
Pregunta
Catalyst poisons increase the surface area for reactants to attach to.
Pregunta 11
Pregunta
Which of the following definitions for heterogenous catalyst is correct?
Respuesta
-
A catalyst is a substance which speed up the rate of the reaction by lowering the activation energy. The catalyst itself is not used up in the reaction. Heterogenous means the catalyst is at a different state to the reactants. For example in a catalytic converter the catalyst is solid whereas the reactants are gases.
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A catalyst is a substance which speed up the rate of the reaction by lowering the activation energy. The catalyst itself is not used up in the reaction. Heterogenous means the catalyst is at the same state to the reactants. For example in a catalytic converter the catalyst is solid whereas the reactants are gases.
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A catalyst is a substance which speed up the rate of the reaction by highering the activation energy. The catalyst itself is used up in the reaction. Heterogenous means the catalyst is at a different state to the reactants. For example in a catalytic converter the catalyst is solid whereas the reactants are gases.
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A catalyst is a substance which slows down the rate of the reaction by lowering the activation energy. The catalyst itself is not used up in the reaction. Heterogenous means the catalyst is at a different state to the reactants. For example in a catalytic converter the catalyst is solid and the reactants are also solids.
Pregunta 12
Pregunta
What is set up in a Br2 molecule when it comes into close proximity with an alkene?
Respuesta
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Induced dipole
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Deduced dipole
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Simple induced dipole
Pregunta 13
Pregunta
Why is a dipole set up in in a Br2 molecule when it comes into close proximity with an alkene?
Respuesta
-
Due to the high electron density in the C=C of the alkene.
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Due to the high electron density in the C-H of the alkene.
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Due to the trend in reactivity between a halogen and a carbon atom
Pregunta 14
Pregunta
What does the dipole mean in a Br2 molecule
Respuesta
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The electrons shared between the Br2 move closer to the furthest Br from the alkene. Forming two areas of charge.
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The covalent bond in the C=C and donates an electron pair to the Br2.
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Lone pairs in the Br2 molecule closest to the alkene are forced towards the covalent bond causing the molecule to split into two Br- ions.
Pregunta 15
Pregunta
Which of the following are electrophiles?
Pregunta 16
Pregunta
An electrophile is a species, which is either a [blank_start]positive[blank_end] ion or has a [blank_start]partially[blank_end] charged element. An electrophile is attracted to an area of [blank_start]high electron density[blank_end]. For example, the C=[blank_start]C[blank_end] double bond.
Respuesta
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positive
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partially
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high electron density
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C
Pregunta 17
Pregunta
Label the electrophillic addition mechanism diagram below.
~The label in the corner, is there for you to name which addition reaction the mechanism is showing~
Respuesta
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Alkene
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Induced dipole
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Carbocation
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Electrophile
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Alkane
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Bromination
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Hydrogenation
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Hydration
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Hydrobromination
Pregunta 18
Pregunta
A full headed curly arrow, in the annotation of an electrophillic addition mechanism, means what?
Respuesta
-
The movement of a pair of electrons
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The movement of an electron
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Specifically the movement of charge
Pregunta 19
Pregunta
What ions are formed after the addition of Br? (Hint only one Br out of the Br2 has bonded to the organic molecule).
Respuesta
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Br- and C+
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Br+ and C-
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Br+ and C+
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Br- and C-