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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. 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.

8 Use this information to calculate the relative atomic mass of copper in this sample. (3) relative atomic mass of copper =... Q3. The positions of five elements, A, B, C, Dand E, are shown in the periodic table. These letters are not the atomic symbols of these elements. (a) Use only elements A, B, C, Dand Eto answer (i) and (ii). (i) Give the letters of allthe elements that are metallic. (ii) Give the letters of the twoelements that have the most similar chemical properties.

9 (b) An atom of element Bcontains more protons than an atom of element A. State how many more protons there are in an atom of element Bthan in an atom of element A. (c) An atom of element Ehas atomic number 10 and mass number 22. (i) How many electrons does this atom contain? Put a cross ( ) in the box next to your answer. A 10 B 12 C 22 D 32 (ii) 10% of the atoms in a sample of element Ehave a mass number of 22. All the other atoms in this sample have a mass number of 20. Calculate the relative atomic mass of element E. (3) relative atomic mass = (d) The element below Ein the periodic table is used to fill filament light bulbs. Explain why this element is suitable for this use. (Total for Question is 9 marks)

10 Q4. Nitrogen and oxygen are present in the air. (a) In industry, nitrogen and oxygen are obtained from air. (i) Give the name of the process used (ii) State why the air is cooled before the start of the process (b) Complete the sentence by putting a cross ( ) in the box next to your answer. Oxygen has a low boiling point because there are A weak covalent bonds between the oxygen atoms B weak covalent bonds between the oxygen molecules C weak forces of attraction between the oxygen atoms D weak forces of attraction between the oxygen molecules (c) Another gas present in air is carbon dioxide, CO 2. There are covalent bonds between the atoms in a molecule of carbon dioxide. (i) Describe what is meant by acovalent bond

11 (ii) The electronic configuration of oxygen (atomic number 8) is 2.6. Give the electronic configuration of carbon (atomic number 6). (iii) Draw a dot and cross diagram of a molecule of carbon dioxide. Show outer electrons only. (Total for Question = 8 marks) Q5. Boron exists as two isotopes. These are boron-10, 10 5B, and boron-11, 11 5B. (a) The diagram shows an atom of the isotope, boron-10.

12 (i) State the electronic configuration of boron (ii) Complete the sentence by putting a cross ( ) in the box next to your answer. In the periodic table, boron is in period A 2 B 3 C 5 D 10 (iii) The table shows the three particles present in atoms and their relative masses and charges. Complete the table. particle electron relative mass relative charge neutron proton +1 *(b) A sample of boron contains 20% boron-10 and 80% boron-11. In part (a) you were given the structure of a boron-10 atom. Describe the structure of a boron-11 atom and explain why, in this sample, boron has a relative atomic mass of (6)

13 (c) Mendeleev was a Russian chemist who produced the first version of the periodic table. Give one similarity and one difference between his version of the periodic table and the periodic table shown on page (Total for Question is 12 marks)

14 Q6. Boron exists as two isotopes. These are boron-10, 10 5B, and boron-11, 11 5B. * A sample of boron contains 20% boron-10 and 80% boron-11. In part (a) you were given the structure of a boron-10 atom. Describe the structure of a boron-11 atom and explain why, in this sample, boron has a relative atomic mass of (6)

15 Q7. Metal atoms The table shows some information about four metals. metal atomic number electronic configuration lithium sodium 11 magnesium calcium (a) State the electronic configuration of sodium (b) Magnesium and calcium are in the same group of the periodic table. Explain why they are both in the same group (c) Complete the sentence by putting a cross ( ) in the box next to your answer. The atomic number of an element is equal to the number of A neutrons in the nucleus of its atom B electrons in the nucleus of its atom C protons in the nucleus of its atom D protons and neutrons in the nucleus of its atom (d) Which of these statements is correct about the particles in atoms? Put a cross ( ) in the box next to your answer.

16 A a proton has the same mass as an electron B an electron is heavier than a proton C a neutron is lighter than an electron D a neutron has the same mass as a proton (e) A lithium atom contains charged particles and yet the atom has no overall charge. Explain why 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 incorrect number of electrons in the

17 (b)(i) A description including any two of 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.

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19 Q3. Answer Acceptable answers Mark (a)(i) A, B and C Mg Ca Au (any order) magnesium calcium gold (any order) (a)(ii) A and B Mg Ca (any order) magnesium calcium (any order) (b) 8 (protons) (c)(i) A : 10 (c)(ii) (in 100 atoms) (3) (d) mass of mass number 20 atoms = mass of mass number 22 atoms = relative atomic mass = {(22 10) + (20 90)}/100 (=20.2) OR 20 contributes = 90/ contributes = 10/ relative atomic mass 90/ /100 x 22 (= 20.2) An explanation linking any two of (the element is) group 0 / noble gas /unreactive / inert / does not react {(has) 8 electrons / full} outer shell prevents filament from reacting 20.2 = 3 marks 21.8 = 2 marks (only 1 error made) ignore 'not very reactive' does not {gain / lose / share} electrons Q4. Answer Acceptable answers Mark (a)(i) fractional distillation (a)(ii) to make it liquid liquefy/condense to remove water (vapour) to remove carbon dioxide (b) D weak forces of attraction between the oxygen molecules (c)(i) An description including Ignore reference to complete/full

20 M shared (electrons) pair(s) of electrons (between atoms) shells Ignore reference to between two metals Ignore reference to between metal and non-metal Ignore reference to between molecules Any reference to between ions scores 0 (c)(ii) 2.4 (c)(iii) diagram showing Must have O C O arrangement any shared pair of electrons between a carbon and oxygen atom in CO 2 molecule If any atom labelled must be correct rest of molecule correct Ignore inner electrons even if wrong electrons can be on/in ring or no ring Ignore intersecting circles Accept all permutations of dots and crosses Q5. Answer Acceptable answers Mark (a)(i) 2.3 (a)(ii) A (a)(iii) 4 correct = 2 marks 2/3 correct = 1 mark 1/0 correct = 0 mark Indicative Content QWC *(b) An explanation linking some of the following Structure of boron-11 boron-11 atom has (

21 5 /same number of protons 5 /same number of electrons 6 neutrons / one more neutron than boron 10 Working out RAM relative atomic mass is 10.8 because OR weighted mean more boron-11 than boron-10 boron-11 atoms are heavier (therefore) relative atomic mass nearer 11 tha in sample given 20/100 of the atoms have a m in sample given 80/100 of the atoms have a m 20/100*10=2 80/100*11= =10.8 NB the diagram in part (a) gives the structure for boro not give credit for this (even if claimed to be structure by referring to it as 'it') Level 0 No rewardable content a limited description e.g. boron-11 has 5 protons and 6 neutrons the answer communicates ideas using simple language and uses limited scientific terminology spelling, puncuation and grammar are used with limited accuracy a simple explanation e.g. boron-11 has 5 protons, 5 electrons and 6 neutrons and is heavier than boron-10. 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 a detailed explanation e.g. boron-11 has 5 protons, 5 electrons and 6 neutrons, is heavier than boron-10 and there is more of boron-11 therefore relative atomic mass nearer to 11 than 10. the answer communicates ideas clearly and coherently uses a range of scientific terminology accurately spelling, puncuation and grammar are used with few errors (c) Answer Acceptable answers Mark Answer should include one idea reverse argument for modern from each list periodic table similarities both put specific examples e.g germanium elements into groups / periods elements with similar properties in same group metals and non-metals in separately

22 M differences Mendeleev's table was arranged by relative atomic mass had gaps had fewer elements did not include the noble gases Q6. Indicative Content QWC * An explanation linking some of the following Structure of boron-11 boron-11 atom has ( 5 /same number of protons 5 /same number of electrons 6 neutrons / one more neutron than boron 10 Working out RAM relative atomic mass is 10.8 because OR weighted mean more boron-11 than boron-10 boron-11 atoms are heavier (therefore) relative atomic mass nearer 11 tha in sample given 20/100 of the atoms have a m in sample given 80/100 of the atoms have a m 20/100*10=2 80/100*11= =10.8 NB the diagram in part (a) gives the structure for boro not give credit for this (even if claimed to be structure by referring to it as 'it') Level 0 No rewardable content a limited description e.g. boron-11 has 5 protons and 6 neutrons the answer communicates ideas using simple language and uses limited scientific terminology

23 spelling, puncuation and grammar are used with limited accuracy a simple explanation e.g. boron-11 has 5 protons, 5 electrons and 6 neutrons and is heavier than boron-10. 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 a detailed explanation e.g. boron-11 has 5 protons, 5 electrons and 6 neutrons, is heavier than boron-10 and there is more of boron-11 therefore relative atomic mass nearer to 11 than 10. the answer communicates ideas clearly and coherently uses a range of scientific terminology accurately spelling, puncuation and grammar are used with few errors Q7. Question Answer Acceptable answers Mark Number (a) any separation allowed Question Number (b) Answer Acceptable answers Mark An explanation linking two of the following points both have two electrons in outer shell (therefore) in group 2 Question Answer Acceptable answers Mark Number (c) C Question Answer Acceptable answers Mark Number (d) D Question Number (e) Answer Acceptable answers Mark An explanation linking the following points

24 Powered by TCPDF ( {equal numbers of / three} protons and electrons (in atoms) proton (charge) +1 and electron (charge) -1