OCR A2 Organic Chemistry

A chemist compares the rates of hydrolysis of 1-chloropropane and 1-bromopropane in ethanol. Which reagent in aqueous solution should be used?

How can this molecule be described?

Complete combustion of an organic compound forms 40cm³ of carbon dioxide and 40cm³ of water vapour, under the same conditions of temperature and pressure. Which molecular formula could the organic compound have?

Which molecule is a Z-isomer?

Which type of reaction has the greatest atom economy?

Four atoms, 1-4, are labelled in the structure to the left. Which atom has a trigonal planar arrangement of bonds around it?

Which molecule is a secondary amine?

What is the number of chiral centres in this molecule?

What is the molecular formula of this molecule?

Equal amounts of the four compounds are added to the same volume of water. Which compound would produce the most acidic solution?

0.1 mol of HOOCCH₂COOH are reacted with 0.1 mol of aqueous NaOH. How many molecules of water are formed?

Which reagents could be used to prepare CH₃CH₂CONHCH₃?

Ethane reacts with chlorine by radical substitution to form chloroethane. Which radical(s) is/are present in the mechanism? 1) H• 2) Cl• 3) C₂H₅•

Which compound(s) is a/are structural isomer(s) of C₆H₁₂O₂? 1) hexanoic acid 2) ethyl butanoate 3) propyl propanoate

Compound A and compound B are isomers. Compound A has a lower melting point than compound B. Suggest why. Compound A is branched so has less points of [blank_start]contact[blank_end] and less surface interaction between the molecules. Therefore, induced [blank_start]dipole-dipole[blank_end] interactions ([blank_start]London forces[blank_end]) are weaker and [blank_start]require less energy[blank_end] to break.

Compound C, CH₃CH₂CH=CHCH₂CH₂OH, exists as cis and trans stereoisomers. Name compound C. [blank_start]Hex-3-en-1-ol[blank_end]

Define the term "stereoisomers" Two molecules that have the same [blank_start]structural formula[blank_end] and a different [blank_start]spatial arrangement[blank_end] of atoms.

Label the cis and trans stereoisomers of compound C.

Compound D, shown below, reacts with hydrogen bromide by electrophilic addition. A mixture of two organic compounds, E and F, is formed. Suggest how an HBr molecule can act as an electrophile. The [blank_start]hydrogen[blank_end] atom of HBr accepts [blank_start]a pair of electrons[blank_end]

What is the systematic name of this organic compound?

Ethanol is oxidised to ethanoic acid using acidified potassium dichromate(IV) solution. The reaction is heated under reflux. What is the reason for heating under reflux?