Loading...
Sec 4 Pure Chem TYS MCQ 2020 Set B
Quiz by HAO YI
Tag the questions with any skills you have. Your dashboard will track each student's mastery of each skill.
Oxygen is prepared by the decomposition of hydrogen peroxide, in the presence of manganese(IV) oxide. The oxygen is collected as shown in the diagram.
Which substance contaminates the first few tubes of oxygen collected?
hydrogen peroxide
nitrogen
hydrogen
manganese(IV) oxide
When an excess of dilute acid is added to a known quantity of sodium carbonate, the temperature of the mixture changes.
An experiment is designed to measure the temperature change when all the carbonate reacts with the acid.
In addition to a thermometer and measuring cylinder, the following pieces of apparatus are available.
1 gas syringe
2 stopwatch
3 balance
4 Styrofoam beaker
Which pieces of apparatus are needed for this experiment?
Oxygen is prepared by the decomposition of hydrogen peroxide, in the presence of manganese(IV) oxide. The oxygen is collected as shown in the diagram.
Which substance contaminates the first few tubes of oxygen collected?
The following substances are used in the laboratory to test for various ions and gases.
When testing for ammonia, chlorine, hydrogen and oxygen, what is the minimum number of items form the table above needed to identify these four gases?
A colourless substance is made in an experiment.
Which are possible methods to determine if this substance is pure?
1 Measure the melting point of the substance and compare with the reference value.
2 Measure the boiling point of the substance and compare with the reference value.
3 Test the substance using paper chromatography and a locating agent.
The rate of diffusion of two gases is measured at different temperatures but at constant pressure.
Which would diffuse most quickly?
Which two substances have similar three-dimensional arrangements of their atoms?
Which compound contains the highest percentage of sulfur by mass?
The formula of an oxide of element Y is Y2O3.
8.0g of Y2O3 contains 5.6g of Y.
How many moles of Y does 5.6 g of the element contain?
Three different compounds are electrolysed.
Which experiments produce a gas at the negative electrode?
The diagram shows a cell.
Which statement about the cell is correct?
A reversible reaction is exothermic in the forward direction and the heat given out is 196 kJ/mol.
The activation energy for the forward reaction is 75 kJ/mol.
What is the activation energy of the reverse reaction?
The energy profile diagram for a reaction is shown.
A catalyst was added and no other reaction condition was changed.
Which energy profile diagram is correct for the catalysed reaction?
A sample of 0.5 g of magnesium ribbon is reacted with an excess of 1 mol/dm3 hydrochloric acid.
The volume of hydrogen produced over time is measured.
The results are plotted to give graph 1.
Which graph would be produced when 0.5 g of magnesium ribbon is reacted with an excess of 2.0 mol/dm3 hydrochloric acid under the same conditions?
Colour changes are often observed when redox reactions occur.
Which colour change is due to the reduction of the named reagent?
Dilute sulfuric acid is added to separate samples of solid substances.
Which row is correct?
Given a supply of lead carbonate, copper(II) carbonate and aqueous sodium hydroxide, how many different salts could be prepared?
A salt can be prepared by adding an excess of solid X to an aqueous solution of Y. A solution and some solid X remain.
The mixture is filtered. The filtrate is evaporated to form a concentrated solution, which is left to crystallise. Excess solution is poured off, leaving salt Z.
Which salt can be safely prepared using this method?
Ammonia can be displaced from its salts.
Which equation is correct?
The diagram shows part of the Periodic Table.
Which two elements would react together most vigorously?
Which statement about transition element is correct?
In the catalytic converter of a car, what type of chemical reaction takes place to change the harmful exhaust gases, carbon monoxide and nitrogen monoxide, into less harmful gases?
Which process removes carbon dioxide from the atmosphere?
A liquid mixture contains a hydrocarbon and water. The boiling points and densities of the hydrocarbon and of water are shown in the table.
Which statements about this liquid mixture can be deduced?
1 The hydrocarbon will form a layer below the water layer.
2 The hydrocarbon is methane.
3 The mixture can be separated using a separating funnel.
How many electrons are involved in the bonding between carbon and one of the oxygens in carbon dioxide, CO2, and between carbon and oxygen in ethanol, C2H5OH?
Each of the following solutions has a concentration of 1mol/dm3.
Which solution contains the greatest number of ions in 1 dm3 of solution?
What is the general formula for the alkenes homologous series?
A compound has the formula C4H10.
Which statement about this compound is correct?
Which statements about the cracking of hydrocarbons are correct?
1 Cracking involves breaking down hydrocarbon molecules.
2 One of the products of cracking is always unsaturated.
3 Cracking is essential because of the demand for fractions containing samller molecules.
Which row shows the products of the complete combustion of ethene and the products of the reaction of ethene with chlorine?
Compound Z
- has the empirical formula CH2
- has an Mr of 56
- reacts with steam to form two alcohols that have different structural formulae.
What is compound Z?
The flow chart shows some of the reactions of organic compounds.
Which row describes the types of reactions involved?
Two compounds, X and Y, react together to form the polymer nylon.
What is the formula of the partial structure which repeats within the polymer?
Which alloy of iron is used in surgical instruments?
