Physical Sciences Grade 10 P2 Gauteng June 2022 Memo (Eng)

Downloaded from hlayiso.com PROVINCIAL EXAMINATION JUNE 2022 GRADE 10 MARKING GUIDELINES PHYSICAL SCIENCES (CHEMISTRY) (PAPER 2) 5 pages

Downloaded from hlayiso.com PHYSICAL SCIENCES (CHEMISTRY) MARKING GUIDELINES (Paper 2) GRADE 10 QUESTION 1: MULTIPLE-CHOICE QUESTIONS 1.1 C ✓✓ (2) 1.2 B ✓✓ (2) 1.3 B ✓✓ (2) 1.4 D ✓✓ (2) 1.5 A ✓✓ (2) [10] QUESTION 2 2.1 A thermal conductor allows heat to pass through easily whereas an electrical conductor allows electric current/electric charges to pass through easily. ✓✓ (2) 2.2 2.2.1 Copper ✓ or nickel (1) 2.2.2 Nickel ✓ (1) 2.2.3 Carbonated water ✓ (1) 2.2.4 Glass ✓or air or Carbon dioxide (1) [6] 2

Downloaded from hlayiso.com PHYSICAL SCIENCES (CHEMISTRY) MARKING GUIDELINES (Paper 2) GRADE 10 QUESTION 3 3.1 The temperature at which the vapour pressure of the substance equals the atmospheric pressure. ✓✓ (2) 3.2 Thermometer ✓ (1) 3.3 Time ✓ (1) 3.4 Graph of temperature against time 90 80 80 70 temperature 60 (°C) 50 40 30 20 10 0 l l l l l l l l -10 5 10 15 20 25 30 35 40 time (min) ✓Heading ✓Axes quantity and unit ✓Intervals ✓Plot ✓Best fit line (5) 3.5 The water is boiling/has reached boiling point/Evaporation. ✓ (1) 3.6 The temperature is constant meaning that the liquid is changing into steam. ✓ The kinetic energy stays constant. ✓ The potential energy is increasing. ✓ (3) [13] 3

Downloaded from hlayiso.com PHYSICAL SCIENCES (CHEMISTRY) MARKING GUIDELINES (Paper 2) GRADE 10 QUESTION 4 4.1 Atoms of the same element having the same number of protons, but different numbers of neutrons. ✓✓ (2) 4.2 4.2.1 1✓ (1) 4.2.2 0✓ (1) 4.2.3 2✓ (1) 4.2.4 1✓ (1) (99,985 𝑥 1)+(0,015 𝑥2)✓ 4.3 Ar(H) = = 1,00015✓ 100✓ (3) [9] 4

Downloaded from hlayiso.com PHYSICAL SCIENCES (CHEMISTRY) MARKING GUIDELINES (Paper 2) GRADE 10 QUESTION 5 5.1 Covalent bond ✓, the sharing of electrons between hydrogen and oxygen to form a water molecule. ✓ (2) 5.2 ✓n=1 ✓n = 2 (2) 5.3 1s2 ✓2s2 2p6 ✓ (2) 5.4 ✓ 6 valence electrons around each O ✓ double bond (2) [8] QUESTION 6 6.1 Energy needed per mole to remove an electron(s) from an atom in the gaseous phase. ✓✓ (2) 6.2 He has a higher ionisation energy than Ne ✓ because He is a smaller atom than Ne ✓ or the energy needed to remove an electron from He is more or the protons of He have a greater attraction force on the electrons than on Ne. (2) [4] TOTAL: 50 5