Esters
5 marks · EasyEsters such as propyl methanoate have distinctive smells and are made by reacting an alcohol with a carboxylic acid.
State the name of the alcohol and the carboxylic acid used to form propyl methanoate.
Draw the displayed formula of propyl methanoate, showing all atoms and bonds.
State one use of esters such as propyl methanoate.
Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.
Show answer
(a) Propyl methanoate forms from propanol and methanoic acid
(b) Displayed formula: HCOOCH2CH2CH3, fully displayed (all bonds and atoms shown) · must show all atoms and bonds, correct connectivity
(c) Used as a flavouring or perfume
Show mark scheme and worked solution
Marking points
B1 (a) · 1 mark · Identifies propanol as the alcohol
B2 (a) · 1 mark · Identifies methanoic acid as the acid
B3 (b) · 1 mark · Correct backbone for propyl methanoate
B4 (b) · 1 mark · All atoms and bonds shown
B5 (c) · 1 mark · States a correct use (flavouring/perfume)
Worked solution
(a) Alcohol: propanol; Acid: methanoic acid
(b) The displayed formula is:
All hydrogen atoms and all bonds should be shown.
(c) Esters such as propyl methanoate are used as flavourings or perfumes because of their pleasant smell.