0620_m24_qp_32
A paper of Chemistry, 0620
Questions:
7
Year:
2024
Paper:
3
Variant:
2

Login to start this paper & get access to powerful tools

1
2
3
4
5
Samarium is a metal. Deduce the number of electrons and neutrons in the samarium atom shown. 154Sm number of electrons number of neutrons  Samarium has properties that are similar to the properties of transition elements. Choose one statement about samarium that is correct. Tick (✓) one box. Compounds of samarium are colourless. Samarium has a low melting point. Samarium and its compounds do not act as catalysts. Samarium has a high density.  Large pieces of samarium react with cold water to produce hydrogen gas. 2Sm + 6H2O → 2Sm(OH)3 + 3H2 Complete by drawing the apparatus to show how the volume of hydrogen gas is measured during this reaction. cold water large pieces of samarium  The experiment is repeated using hot water instead of cold water. All other conditions stay the same. Describe how the rate of reaction changes when hot water is used. The experiment is repeated using powdered samarium instead of large pieces of samarium. All other conditions stay the same. Describe how the rate of reaction changes when powdered samarium is used. Table 5.1 shows the observations when samarium and three other metals are heated in oxygen. Table 5.1 metal observations nickel reacts very slowly samarium reacts rapidly strontium reacts very rapidly yttrium does not react Put the four metals in order of their reactivity. Put the least reactive metal first. least reactive most reactive  Samarium reacts with oxygen to produce samarium oxide, Sm2O3. Complete the symbol equation for this reaction. Sm + 3O2 → Sm2O3 Hydrated samarium chloride is an ionic compound. Define the term hydrated. State two physical properties of an ionic compound.  
6
Sulfur is an element in Group VI of the Periodic Table. State the meaning of the term element. Sulfur has a relative atomic mass of 32. Complete these sentences about the relative atomic mass of sulfur using terms from the list. 12C electrons 1H isotopes neutrons 16O protons 32S The relative atomic mass of sulfur is the average mass of the sulfur . This average mass is compared to 1/12th of the mass of an atom of .  Sulfur is a solid at room temperature and pressure. Describe the motion and separation of the particles in solid sulfur. motion separation  Liquid sulfur reacts with chlorine to produce disulfur dichloride. 2S + Cl 2 → S2Cl 2 Describe how the general physical properties of a liquid differ from those of a solid. Give two differences.  When 6.4 g of sulfur reacts with excess chlorine, 13.5 g of disulfur dichloride is produced. Calculate the mass of disulfur dichloride produced when 19.2 g of sulfur reacts with excess chlorine.  mass = g Sulfur dioxide is formed when sulfur burns in air. State the percentage of oxygen in clean, dry air. State one source of the pollutant sulfur dioxide in the air other than from burning sulfur. State one adverse effect of sulfur dioxide in the air. State one method of reducing the emissions of sulfur dioxide. Sulfur dioxide dissolves in water to form sulfurous acid. Give the formula of the ion that is present in all aqueous acids. Sulfur dioxide reacts with oxygen in the presence of a catalyst to form sulfur trioxide. This is a reversible reaction. Complete the equation for this reaction by writing the sign for a reversible reaction in the box. 2SO2 + O2 2SO3 
7