Snakes and Ladders Questions
1Q Name an alcohol.A. methanol, ethanol, propanol, butanol, etc. / 2Q What is the functional group of an alcohol?
A. -OH- / 3Q What is the molecular formula of butanol?
A. H H H H
l l l l
H-C-C-C-C-O-H
l l l l
H H H H / 4Q What is produced when propanol reacts with sodium?
A. sodium propanoate
1Q What are esters used for?
A. In food as flavourings and in perfumes. / 2Q Name the chemical that is always produced when an ester is made.
A. Water / 3Q Write down the word equation for making ethyl propanoate.
A. ethanol + propanoic acid =
ethyl propanoate + water / 4Q Write down the structural formula of ethyl propanoate.
A. H H O H H
l l ll l l
H-C-C-O-C-C-C-H
l l l l
H H H H
1Q Alkanes are unsaturated. True or false?
A. False / 2Q Write down the structural formula for propane.
A. H H H
l l l
H-C-C-C-H
l l l
H H H / 3Q Write a balanced equation for ethane burning in a good supply of air.
A.
2C2H6 + 7O2 =
4CO2 + 6H2O / 4Q Write a balanced equation for ethane burning in a limited supply of air.
A.
2 C2H6 + 5O2 =
4CO + 6H2O
1Q What type of compound is a fat?
A. An ester. / 2Q Which alcohol reacts with fatty acids to make fats?
A. Glycerol. / 3Q Name the two types of reagent needed to make a fat.
A. A fatty acid and an alcohol. / 4Q Explain the difference between a saturated and an unsaturated fat.
A. Saturated - only single bonds between C-C atoms, unsaturated have some double bonds, C=C.
1Q What does exothermic mean?
A. Energy is released during a reaction. / 2Q Burning diesel is an endothermic reaction. True or false?
A. False. / 3Q Why is energy needed to start a reaction?
A. To break bonds in the reactants. / 4Q In an exothermic reaction what can you say about the bond breaking process compared with the bond making process?
A. More energy is released on making the bonds then is needed to break the bonds.
Snakes and Ladders Questions
1Q Name the acid contained in vinegar.A. Ethanoic acid / 2Q What is the functional group of a carboxylic acid?
A. COOH, CO2H or
/ 3Q Name the two substances formed when an alkali reacts with a carboxylic acid?
A. A salt and water / 4Q If an alkane containing 8 carbon atoms is called octanol what is the acid which contains 8 carbon atoms called?
A. Octanoic acid
1Q What is needed to break the bonds in a reaction?
A. Energy / 2Q What is the activation energy?
A. The minimum energy needed in a collision between reactants for a reaction to take place. / 3Q Do all collisions between particles lead to a reaction?
A. Only those collisions between particles which have energy equal to or greater than the activation energy. / 4Q Draw an energy level diagram for an exothermic reaction.
1Q Weak acids may have a pH of ?
A. 5 or 6 / 2Q Name a weak acid.
A. Any carboxylic acid, e.g. ethanoic acid or citric acid. / 3Q Why is hydrochloric acid described as a strong acid?
A. In water it splits up completely into ions. / 4Q This represents a dynamic equilibrium. What does this mean?
CH3COOH(aq) + H2O(l)
<=> CH3COO-(aq) + H+(aq)
A. Forward and back reaction occurring at the same rate. No overall change.
1Q Name 3 types of chromatography.
A. Paper, thin layer (TLC) and gas. / 2Q Explain stationary phase and mobile phase.
A. Stationary-an absorbent solid which does not move. Mobile-a solvent which moves. / 3Q What is the retardation factor (Rf)?
A.
distance moved by chemical
distance moved by solvent / 4Q Why are some mobile phases better at separating a mixture than others?
A. Some substances are more soluble in some solvents than others.
1Q How could you improve the separation of a mixture by chromatography ?
A. Find a more suitable solvent. / 2Q In chromatography what are standard reference materials?
A. Substances added to the chromatogram that are suspected of being in the unknown mixture. / 3Q On running a chromatogram why is it important to mark the solvent front?
A. So that the Rf value of the substances can be calculated and then identified. / 4Q If the solvent front has moved 8cm and the unknown substance 7.2cm, what if the Rf value?
A. 7.2/8.0 = 0.9
Snakes and Ladders Questions
1Q Name the main sugar which is fermented to make ethanol.A. Glucose. / 2Q Fermentation is an anaerobic reaction. Explain.
A. A reaction which takes place without oxygen. / 3Q Explain why fermentation does not take place above 37oC
A. Above this temperature the enzymes in the yeast are denatured and do not work. / 4Q Why does fermentation produce aqueous solutions of ethanol containing a maximum of 14%ethanol.
A. Above this concentration the ethanol is toxic to the yeast.
1Q Which apparatus is used to transfer an accurate fixed volume of liquid to a flask?
A. Pipette. / 2Q Name the apparatus used to hold the acid in a titration between an acid and an alkali?
A. Burette / 3Q What is the aim of a qualitative technique? Specific use ?
A. To find out the chemical composition of a specimen. / 4Q What is the end-point of a titration and what is used to show it?
A. To completely react together 2 reagents.
An indicator.
1Q What is a catalyst?
A. A substance which speeds up the rate of a reaction without being used up or changed chemically. / 2Q Which two factors are used as a measure of the efficiency of an industrial process?
A. Atom economy, percentage yield. / 3Q Why do chemists use a catalyst in an industrial process?
A. To provide an alternative route which reduces the time taken and the amount of energy used. / 4Q Explain the meaning of atom economy.
A.
Mass of atoms in product x100
Mass of atoms in reactants
1Q Name the main source of chemical feedstocks used at the moment.
A. Crude oil. / 2Q What is a fine chemical?
A. Chemical made by industry on a very small scale. / 3Q How does the Chemical Industry intend to make itself greener and more sustainable?
A. Use renewable raw materials and not use crude oil. / 4Q Give ways of reducing “waste” in an industrial process.
A. Find uses for the by-products, recycle at all possible stages, use efficient process which have high atom economy.
1Q How do you calculate the mean value?
A. Add together the set of results and then divide by the number of results. / 2Q What is accuracy?
A. It describes how close the result is to the actual value. / 3Q If a set of results is precise what does this tell you?
A. There is only a small spread between the measured values. / 4Q For a scientist to draw a conclusion from his work it must be valid. What does valid mean?
A. The techniques and procedures used were suitable for the task.