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6 Questions Q1. Lithium, sodium and potassium are metals in group 1 of the periodic table. They are good conductors of heat and electricity. The freshly-cut metals are shiny. (a) (i) Give another physical property of all three of these metals. (ii) Explain, in terms of electrons in their atoms, why lithium, sodium and potassium are in group 1 of the periodic table. (b) A small piece of potassium is added to water. (i) Describe what you would seein this reaction. (ii) Which of these is the balanced equation for this reaction? Put a cross ( ) in the box next to your answer. A 2K + 2H 2 O K 2 O + 2H 2 B 2K + H 2 O K 2 O + H 2 C 4K + 3H 2 O 4KOH + H 2 D 2K + 2H 2 O 2KOH + H 2 (c) There is an increase in reactivity of these group 1 metals from lithium to potassium. Explain this increase in reactivity. (Total for Question is 8 marks)

7 Q2. Elements Mendeleev produced the first periodic table. In a version of his periodic table, he put these elements in group 1. hydrogen lithium sodium potassium copper rubidium silver caesium gold (a) Some of the elements in this list are also in group 1 of the modern periodic table. Which element is in the list above and also in group 1 of the modern periodic table? Put a cross ( ) in the box next to your answer. A gold B silver C copper D sodium (b) The element francium is now included in group 1 of the modern periodic table but did not appear anywhere in Mendeleev s periodic table. Suggest why francium was not in Mendeleev s periodic table.

8 (c) Explain why hydrogen is not included in group 1 in most versions of the modern periodic table (d) The atomic number and electronic configurations of three elements are shown in the table below. element atomic number electronic configuration lithium sodium potassium Describe how the electronic configuration of sodium shows the group and period of sodium in the periodic table *(e) An atom of beryllium has an atomic number of 4 and a mass number of 9. Describe the numbers and arrangements of the protons, neutrons and electrons in this atom. (6)...

9 Q3. * An atom of beryllium has an atomic number of 4 and a mass number of 9. Describe the numbers and arrangements of the protons, neutrons and electrons in this atom. (6)

10 Q4. (a) Complete the sentence by putting a cross ( ) in the box next to your answer. The particles in atoms are electrons, neutrons and protons. The mass of an electron is A greater than the mass of a neutron B the same as the mass of a proton C smaller than the mass of a proton D the same as the mass of a neutron (b) The atomic number of oxygen is 8. The mass number of an atom of oxygen is 17. Describe the number and type of particles in the nucleus of this atom

11 ... (c) Sulfur and oxygen are both in group 6 of the periodic table. Explain, in terms of their electronic configurations, why they are both in group (d) An atom of phosphorus contains 15 electrons. Describe how these 15 electrons are arranged in a phosphorus atom (e) Phosphorus oxide is a compound that contains covalent bonds. (i) Describe what is meant by a covalent bond (ii) The formula of a molecule of phosphorus oxide is P 4 O 10 Give the empirical formula of this oxide.... (Total for Question = 10 marks)

12 Q5. An atom of copper has an atomic number of 29 and a mass number of 63. (i) Complete the table to show the numbers of protons, neutrons and electrons in this atom of copper. (ii) Copper is in period 4 of the periodic table. State what information this gives about the number of shells that contain electrons, in a copper atom.... (iii) Copper exists as isotopes. Explain what is meant by the term isotopes (iv) A sample of copper contains 70% of copper-63 atoms and 30% of copper-65 atoms. Use this information to calculate the relative atomic mass of copper in this sample (3)

13 relative atomic mass of copper =... Q6. (a) The table shows the number of electrons, neutrons and protons in particles P, Q, R, S, T and V. (i) Which particle is a negatively charged ion? Put a cross ( ) in the box next to your answer. A P B S C T D V (ii) Which particles are atoms of metals? Put a cross ( ) in the box next to your answer. A P and R

14 B Q and R C Q and S D Q, S and V (b) Each element has an atomic number. (i) State what is meant by atomic number (ii) The atomic number of boron is 5. Boron exists as two isotopes boron-10 and boron-11. Use this information to explain why boron-10 and boron-11 are isotopes (c) (i) Explain what is meant by the term relative atomic mass

15 (ii) A sample of boron contains 19.7% of boron % of boron-11. Use this information to calculate the relative atomic mass of boron (3) (Total for Question = 10 marks) Q7. (a) The diagram shows an atom of lithium. (i) A proton has been labelled. Complete the diagram by labelling the other two particles shown. (ii) Complete the sentence by putting a cross ( ) in the box next to your answer. The atomic number of lithium is

16 A 3 B 6 C 7 D 10 (b) (i) Which row of the table shows the charge on a proton and the charge on an electron? Put a cross ( ) in the box next to your answer. A B C D proton electro n positive positive negative negative negative positive positive negative (ii) Use a number from the box to complete the sentence. The relative mass of a proton is (c) The electronic configuration of lithium is 2.1. The electronic configuration of sodium is (i) Explain, in terms of their electronic configurations, why lithium and sodium are both in group 1 of the periodic table

17 (ii) Explain, in terms of their electronic configurations, why lithium is placed in period 2 and sodium is placed in period 3 of the periodic table (Total for Question is 9 marks) Q8. Most atoms contain electrons, protons and neutrons. (a) Describe the positions of these particles in atoms (3)

18 (b) A chlorine atom contains 17 electrons. What is the electronic configuration of a chlorine atom? Put a cross ( ) in the box next to your answer. A 10.7 B C 17 D (c) Chlorine and bromine are in the same group in the periodic table. (i) Explain, in terms of electrons, why these elements are placed in the same group (ii) Describe the appearance of bromine at room temperature and pressure (d) An experiment was carried out to see how large a nucleus is compared to the overall size of

19 an atom. In the experiment a very large number of positively charged particles are fired at a thin sheet of gold. When one of these positively charged particles comes close to the nucleus of a gold atom it is repelled. Explain why only about 1 in every positively charged particles are repelled (Total for Question is 10 marks) Mark Scheme Q1. Answer Acceptable answers Mark (a)(i) soft / low melting point / low boiling point easilycut with a knife = soft low density malleable solid at room temp. (a)(ii) An explanation linking (all have) one electron in outer shell ignore float on water reject chemical properties one outer electron = 2 marks group number shows number of electrons in outer shell = 2 marks same number of electrons in outer shell = 1 mark

20 (b)(i) A description including any two of incorrect number of electrons in the outer shell = 1 mark accept outer orbit / highest energy level in place of outer shell effervescence / fizzing / bubbles potassium floats moves (on surface) potassium forms ball / melts potassium decreases in size / ignore ignites disappears / dissolves (lilac) flame / catches fire ignore smoke spits / explodes / sparks (b)(ii) D : 2K + 2 H 2 O 2KOH + H 2 (c) An explanation linking any two of increasing {size /radius (of atom) / number of shells} increased shielding (of outer electron) less attraction for (outer) electron easier to remove (outer) electron Q2. Question Answer Acceptable answers Mark Number (a) D Question Number (b) Answer Acceptable answers Mark had not been discovered did not know about it Question Number (c) Answer Acceptable answers Mark An explanation linking the following points EITHER different properties (to other group 1 elements)

21 elements in a group have similar (chemical) properties OR hydrogen is a non-metal / not a metal all the other elements are metals Question Number (d) Answer Acceptable answers Mark A description including the following points one electron in outer shell so in group 1 (electrons in) three shells so in period 3 Question Indicative content Number QWC *(e) A description including some of the following points Mark (6) four protons five neutrons four electrons protons in nucleus neutrons in nucleus electrons in shells two electrons in first shell two electrons in second/outer shell last two points could be expressed as electronic configuration is 2.2

22 allow correct diagram

23 Level 0 no rewardable material correct number or position of one type of particle / correct numbers or positions or two particles the answer communicates ideas using simple language and uses limited scientific terminology spelling, punctuation and grammar are used with limited accuracy correct number and position of one type of particle and two other correct numbers and /or positions of other particle(s) the answer communicates ideas showing some evidence of clarity and organisation and uses scientific terminology appropriately spelling, punctuation and grammar are used with some accuracy correct number and position of all three particles / one error in former and correct electronic configuration the answer communicates ideas clearly and coherently uses a range of scientific terminology accurately spelling, punctuation and grammar are used with few errors Q3. Question Indicative content Number QWC * A description including some of the following points Mark (6) four protons five neutrons four electrons protons in nucleus neutrons in nucleus

24 electrons in shells two electrons in first shell two electrons in second/outer shell last two points could be expressed as electronic configuration is 2.2 allow correct diagram Level 0 no rewardable material correct number or position of one type of particle / correct numbers or positions or two particles the answer communicates ideas using simple language and uses limited scientific terminology spelling, punctuation and grammar are used with limited accuracy correct number and position of one type of particle and two other correct numbers and /or positions of other particle(s) the answer communicates ideas showing some evidence of clarity and organisation and uses scientific terminology appropriately spelling, punctuation and grammar are used with some accuracy correct number and position of all three particles / one error in former and correct electronic configuration the answer communicates ideas clearly and coherently uses a range of scientific terminology accurately spelling, punctuation and grammar are used with few errors Q4. Answer Acceptable answers Mark (a) C smaller than the mass of a proton

25 (b) An description linking 8 protons (and) {17-8/9} neutrons ignore references to electrons in shells / charges on particles (c) (d) Explanation linking (both have) same number (of electrons) in outer shell 6 (electrons in outer shell) (consequent on first point) A description to include 2.8 (in 1 st and 2 nd shell) 5 (in outer shell) (e)(i) A description to include electron(s) shared {pair(s) of / two} (electrons) if electrons in nucleus max 1 protons and neutrons with incorrect numbers correct electronic configurations or diagrams alone max 1 'they both have 6 in the outer shell' scores both marks allow 'both need 2 (more) (electrons) to fill outer shell' for both marks suitable diagram in place of electrons in {shells / orbits / rings} can be shown in a diagram of a covalent bond any mention of ions scores zero (e)(ii) P 2 O 5 Reject P2O5 / P 2 O 5 Q5.

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27 Q6. Answer Acceptable answers Mark (a)(i) C T (a)(ii) C Q and S (b)(i) number of protons (in nucleus of atom) (b)(ii) An explanation including ignore number of electrons eg number of protons and electrons worth (atoms of) both contain 5 /same number of protons/same atomic number boron-10 atoms contain 5 neutrons but boron-11 atoms contain 6 neutrons / different numbers of neutrons/ different mass number ignore electrons boron-11 atoms contain 1 more neutron / boron-10 atoms contain 1 less neutron (c)(i) An explanation including the following M1 {average/mean} mass (of atoms of an element) For M1 reject weight reject if mass of molecule reject if mass of neutrons and protons any reference to carbon-12 M2 compared to {1/12 mass scores mark carbon-12 (atom)/ (mass of) carbon-12 (atom) taken as 12} (c)(ii) [ ] +[ ] /100 (=10.8) [ ] + [ ] = [ ] (=10.8) If no working shown 10.8(03) worth 3 marks (3) Q7. Answer Acceptable answers Mark (a)(i) neutron neutrons electron electrons

28 (a)(ii) A 3 (b)(i) D proton positive, electron negative (b)(ii) 1 (c)(i) An explanation linking both have one outer electron (both have) one electron in the outer {shell/orbit/energy level} do not award first mark if proton/neutron/atom (in outer shell) both need to lose 1 electron to have a full outer shell fully correct diagrams of lithium and sodium showing electronic configurations (c)(ii) An explanation linking lithium has 2 {shells/orbits/energy levels} sodium has 3 {shells/orbits/energy levels} max 1 mark if {outer/full} shells max 1 mark if rings/circles/layers have the same number of electrons in the outer shell If no marks awarded from 'answer' column, allow any onefrom sodium is more reactive than lithium ORA sodium has more electrons than lithium ORA sodium has more shells than lithium ORA ignore reactivity increases down the group Q8. (a) Answer Acceptable answers Mark A description to include all marks can be scored from (3) labelleddiagram neutrons in nucleus description of position of particles protons in nucleus without use of "nucleus" or "shell /orbit" electrons in shells / orbits BUT if description or labels on diagram do not mention "nucleus" or"shell /orbit"

29 Powered by TCPDF ( at least once then max 2 marks ignore charges / masses / numbers of particles (b) D (c)(i) an explanation linking outer {shell / orbit} (electrons) 7 / same number (of electrons) one / same number of electrons short (of next noble gas) (c)(ii) a description to include red-brown / brown-red (dark) red ignore any references to vapour (d) liquid An explanation linking any two of nucleus very small (by comparison with atom) / atom very large compared to nucleus / most of atom consists of empty space most particles {miss nucleus / go straight through (atom)} / only a few particles (1 in ) {pass close to / hit} nucleus (gold) nuclei positive / both (nucleus and particles) {positively charged / have same charge}