1 Smoking is strictly prohibited in laboratories. Why is smoking not allowed in science laboratories? flag bookmark A May cause chemical contamination B Produces excess carbon dioxide C Can cause a fire of flammable materials D Disturbing other students' focus while an experiment is being conducted T4 Chapter 1.3 Usage, Management and Handling of Apparatus and Materials Smoking involves an open flame or lit ember, which can ignite flammable chemicals commonly found in labs, so it is strictly banned.
2 Based on Diagram 2, which scientist proposed that atoms are small spherical bodies, which cannot be created, destroyed or further divided? flag bookmark A John Dalton B J.J. Thomson C James Chadwick D Ernest Rutherford T4 Chapter 2.2 The Development of the Atomic Model The diagram shows the atom as a single solid sphere, which matches Dalton's model of an indivisible particle that cannot be created or destroyed. Thomson, Chadwick and Rutherford proposed models involving smaller particles inside the atom.
3 What is the main reason carbon-12 atom was chosen as the standard for determining relative atomic mass? flag bookmark A Has 6 electrons in the outermost shell B The lightest element in the Periodic Table of Elements C Form organic compounds in all substances D Exists as solid at room temperature and can be handled easily T4 Chapter 3.1 Relative Atomic Mass and Relative Molecular Mass Carbon-12 is a solid at room temperature, so it can be handled and weighed easily, allowing accurate determination of relative atomic mass for other elements.
4 Which of the following are characteristics of Group 18 elements? I Chemically inert II Colourless and odourless gas III Has two valence electrons IV Exists as solid at room temperature flag bookmark A I and II B I and IV C II and III D III and IV T4 Chapter 4.3 Elements in Group 18 Group 18 elements are chemically inert due to their stable electron configuration and exist as colourless, odourless gases at room temperature. Helium has only 2 valence electrons, and they are not solids, so III and IV are wrong.
5 Diagram 5 shows an illustration of conversation between atom P and atom Q. What is the type of chemical bond that will be formed between atom P and atom Q? flag bookmark A Ionic B Metallic C Dative D Covalent T4 Chapter 5.5 Dative Bond Both P and Q are non-metals, from Group 14 and Group 17, so they share electrons to achieve stable configurations, forming a covalent bond.
6 Table 6 shows the pH values of solutions P, Q, R and S. | Solution | P | Q | R | S | |---|---|---|---|---| | pH | 5 | 6 | 7 | 9 | Which solution is alkaline? flag bookmark A P B Q C R D S T4 Chapter 6.2 pH Value A solution is alkaline when its pH is greater than 7; S has pH 9.
7 Diagram 7 shows the apparatus set-up for an experiment to determine the rate of reaction between calcium carbonate and hydrochloric acid. Which of the following units is suitable for measuring the rate of reaction in this experiment? flag bookmark A g s⁻¹ B cm³ s⁻¹ C mol s⁻¹ D mol dm⁻³ T4 Chapter 7.1 Determining Rate of Reaction The gas produced is collected in the burette, so its volume is measured over time. Hence the rate is in cm³ s⁻¹.
8 What is the main component in bronze? flag bookmark A Iron B Aluminium C Tin D Copper T4 Chapter 8.1 Alloy and Its Importance Bronze is an alloy of copper and tin, with copper as the main metal by proportion.
9 Iron(II) nitrate can act as a reducing agent. What changes occur when iron(II) nitrate reacts with bromine water? flag bookmark A Iron(II) ion, Fe²⁺ turns into bromide ion, Br⁻ B Iron(II) ion, Fe²⁺ accepts electrons to become iron(III) ion, Fe³⁺ C Iron(III) ion, Fe³⁺ accepts electrons to become iron(II) ion, Fe²⁺ D Iron(II) ion, Fe²⁺ loses electrons to become iron(III) ion, Fe³⁺ T5 Chapter 1.1 Oxidation and Reduction Fe²⁺ acts as a reducing agent, so it loses electrons and is oxidised to Fe³⁺. This reduces bromine water.
10 Diagram 10 shows a fruit that contains compound R which has a fruity smell. What is the functional group of compound R? flag bookmark A Carboxylate B Carboxyl C Hydroxyl D Single bond between carbon atoms T5 Chapter 2.2 Homologous Series Esters are the family of compounds responsible for fruity smells, and their functional group is the carboxylate group, so compound R is an ester.