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AP WORKSHEET 01a: Elements, Mixtures & Compounds1. Classify each of the following as either, an element, a compound or a mixture. If you classifysomething as a mixture then also state whether it is a homogeneous or a heterogeneous mixture.(10)(a) Helium(b) Nitrogen(c) Pure water(d) Pure table salt (sodium chloride)(e) Flat (un-carbonated) Coca-Cola(f)Air(g) Fruit cake2. If three, different samples of a particular compound are found to have exactly the same elemental %by mass, what does that tell us about;(a) the three samples in relation to one another? (2)(b) the purity of the three samples? (2)3. Visit the following URL: http://www.darvill.clara.net/multichoice/emc.htm and answer the questionfound there. (11)1

4. Match the following particulate diagrams to the correct description. In each case a black circle and ared circle represent the atoms of different elements. (4)1 2 3 4 5A.A single, pure, monatomic element.B.A mixture of two elements.C.A single, pure compound.D.A mixture of two compounds.E.A mixture of an element and a compound.2

AP WORKSHEET 01b: Empirical Formula1. A common oxide of nitrogen contains 25.93% N. Deduce the empirical formula of the oxide.(2)2. A compound that is usually used as a fertilizer can also be used as a powerful explosive. Thecompound has the composition 35.00% nitrogen, 59.96% oxygen and the remainder beinghydrogen. What is its empirical formula? Given it is ionic, suggest a name for the compound.(3)3. What are the empirical formulae for these compounds, that both contain five carbon atoms?(2)(a) C5H10(b) C5H124. A substance has an empirical formula of CH2Br and a molar mass of 188 g mol-1. What is themolecular formula of the compound? (1)1

5. The common pain medicine, Advil, contains the active ingredient Ibuprofen that has a molarmass of 206 g mol-1. Ibuprofen contains 75.73% C, 8.74% H, the remainder being oxygen.What are the empirical and molecular formulae for Ibuprofen? (4)6. The molar mass of the common antibiotic oxytetracycline is found to be 460 g mol-1 and a2.000 g sample contains 1.1478 g of carbon, 0.10435 g of H, 0.62609 g of oxygen and theremainder being nitrogen. What is the molecular formula of the oxytetracycline? (4)2

AP WORKSHEET 01c: Isotopes and Mass Spectrometry1. Many elements have a number of isotopes.(a) Define the term isotope. (2)(b) Complete the following table. (22)RowIsotope symbolAtomic ## Protons# NeutronsMass #131C621718326564173752652731285070(c) Consider the 2nd and 4th row in the table. What three things do they have in common?(3)(d) Consider the 2nd and 4th row in the table. Give two differences? (2)(e) Naturally occurring Ni is found to have the following approximate isotopic abundance;58Ni 68%, 60Ni 26%, 62Ni 4.0% and 61Ni 2.0%Calculate the average relative atomic mass of Ni to two decimal places. (2)1

2. The results taken from a mass spectrum of chlorine gas show peaks at m/z 35.00 and m/z37.00 (The m/z peaks on a mass spectrum identify the different isotopes of an element thatare present in the sample).(a) Given that the relative abundances of Cl 35.00 and Cl 37.00 are 77.50% and 22.50%respectively, calculate the average relative atomic mass of chlorine atoms to foursignificant figures. (2)(b) Suggest all the possible masses of CI2 molecules that are made when two chlorineatoms bond together. (3)(c) Which of the molecules you have suggested in (b) will be the most abundant? Explainyour answer. (2)2

3. Naturally occurring bromine molecules, Br2 have masses of 158, 160 and 162. They occur inthe relative abundances 25.69%, 49.99% and 24.31% respectively. What is the averageatomic mass of bromine atoms? What is the relative abundance of79Br and 81Br isotopes? (4)4. An unknown element ‘Z’ is analyzed in a mass spectrometer and is found to have thefollowing isotopes with the corresponding relative ativeabundance(a) Using the axis below, sketch the expected mass spectrum that these data wouldprovide. Label the axes and pay attention to the size of any lines that you draw. (4)(b) Calculate the average atomic mass of Z and identify the element. (3)3

5. Consider the following mass spectrum that was generated from the analysis of an element.Relative Abundance100242526272829m/z(a) What does the existence of only a single peak in the spectrum suggest about theelement?(b) Identify the element.6. Copper has an atomic mass of 63.5456 amu and has two stable isotopes. Copper-63 has amass of 62.9296 amu, and copper-65 has a mass of 64.9278 amu.(a) Calculate the percent abundance of each isotope of copper.(b) Sketch the expected mass spectrum of the copper.4

AP WORKSHEET 01d: Quantitative aspects of electrons1. This question is about breaking covalent bonds.(a) The bond energies of the single bonds between two chlorine atoms within a chlorine moleculeand two fluorine atoms within a fluorine molecule are calculated to be 4.02 x 1010-19-19J and 2.64 xJ respectively. For each bond, calculate the following;(i)The frequency of a photon that could be used to break the bond. (2)(ii)The wavelength of each photon in (i). (2)(b) When an excited electron falls back to its ground state, what can be said of the energy changethat occurs when compared to the energy change of the original, promotion process? Explain.(2)2. Lithium ions give a distinctive red flame test. In one such experiment the energy of this red light isfound to have an energy of 3.06 x 10-19 J. Calculate the wavelength of the light from the lithium ions innm. (2)3. Which of the following process will release the greatest amount of energy? Explain your answer. (2)Promoting an electron from n 1 to n 6Promoting an electron from n 1 to n 4An electron falling from n 6 to n 2An electron falling from n 6 to n 54. When an electron falls from n 5 to its lowest possible state in the Lyman series, the energy that isreleased is greater than the energy that is released when an electron falls from n 5 to its lowestpossible state in the Balmer series. Explain. (2)5. Electron transitions are expected to absorb or emit greater magnitudes of energy in the He ionthan in the hydrogen atom. Why? (2)1

AP WORKSHEET 01e: Orbital filling rulesThe rules that you have been applying in order to determine the electronic configuration of an atom are summarized below.A.Lowest energy orbitals are filled first. THE AUFBAU PRINCIPLE.B. Orbitals can only contain a maximum of two electrons and when two electrons enter the same orbital they must have opposite spins ( ½or – ½) so that each electron has a unique set of quantum numbers. (In the electrons in boxes diagram they must be drawn NOT OR ). THE PAULI EXCLUSION PRINCIPLE.C. When orbitals of identical energy (degenerate) are available electrons enter these orbitals singly before any spin pairing takes place.HUNDS RULE.Consider each of the elements listed and the INCORRECT electronic configuration associated with each one. In each case identify which of theabove rules or principles (A, B or C) is violated and insert the correct electronic configuration (in a similar format to that of the incorrectconfiguration). Then add a possible set of quantum numbers for the outer most electron. An example is completed for you. (34)Page 1 of 2

GURATIONN1s2 2s2 2px2 2py1C1s2 2s2 2px1 2py1 2pz1Al1s2 2s2 2p6 3p3B1s2 2s3P1s2 2s2 2p6 3p5[Ne] Mg21C1s 2s 2px1 2py1 2pz1C1s2 2s2 2px2Mn[Ar] 4s1 3d6Ni[Ar] 4s2 3dxy2 3dxz2 3dyz2 3dz22 3dx2-y20Cl[Ne] Sc[Ar] 3d3B1s2 2s1 2px1 2py1Na1s1 2s2 2p6 3s2S[Ne] 3s 3px 3pyV[Ar] 3d5P[Ne] 3s2 3px2 3py1Kr[Ar] 4s2 3d16222Page 2 of 2

AP WORKSHEET 01f: Electronic Configuration Summary1. Give full and abbreviated (noble gas core method) electronic configurations for the following.(8)(a) Br(b) Cr(c) Fe(d) S2-FULLNOBLE GAS COREFULLNOBLE GAS COREFULLNOBLE GAS COREFULLNOBLE GAS CORE2. For each of the following sets of orbitals, indicate which orbital is higher in energy. (4)(a) 1s, 2s(b) 2p, 3p(c) 4s, 3dyz(d) 3px, 3py, 3pz3. Indicate the block (s, p or d) in which each of the following elements found. (5)BLOCK(a) Sc(b) P1

(c) Fr(d) Ni(e) As4. An atom has two electrons with principal quantum number (n) 1, eight electrons withprincipal quantum number (n) 2 and seven electrons with principal quantum number (n) 3.From these data, supply the following values (if insufficient information is given, say so).(a) The mass number. (2)(b) The atomic number. (1)(c) The electron configuration. (2)5. Identify the element from the electron configurations of atoms shown below. (3)(a) [Ne] 3s2 3p2(b) [Ar] 4s2 3d7(c) [Xe] 6s26. Give the symbol of the atom or ion represented by the following sets of atomic numbers andelectronic configurations. (4)Atomic #Electronic ConfigurationSymbol of Atom or Ion(a) 81s2 2s2 2p4(b) 111s2 2s2 2p6(c) 141s2 2s2 2p6 3s2 3p2(d) 221s2 2s2 2p6 3s2 3p6 3d22

7. Give the electron configurations for the following transition metal ions. (3)(a) Sc3 (b) Cr2 (c) Ni3 8. Consider the element Scandium, atomic # 21.(a) If the electronic configuration of the element were constructed "from scratch", into whichorbital (and into which shell) would the final electron be placed? (1)(b) When scandium forms an ion with a charge of 1, from which orbital (and from whichshell) would the electron be removed? (1)9. Of the following species (Sc, Ca2 , Cl, S2-, Ti3 ), which are isoelectronic? (1)10. Identify the element that is composed of atoms where the last electron; (5)(a) Enters and fills the 4s sub-shell(b) Enters but does not fill the 4s sub-shell(c) Is the first to enter the 2p sub-shell(d) Is the penultimate to enter the 4p sub-shell(e) Is the second to enter the 4d sub-shell3

11. Write the full electronic configuration for argon. (1)12. Identify two positive and two negative ions that are isoelectronic with argon. (4)(a) Two Positive ions(b) Two Negative ions13. Using the electrons in boxes notation complete the electronic configurations of the followingelements. (3)1s2s2p3s3p3d4s4pElement V1s3s4s2s2p3p3d4pElement Ar1s3s4s2s2p 3p3d 4pElement Zn14. State the number of unpaired electrons in each of the electronic configurations in question13. (3)# of unpaired electrons(a) V(b) Ar4

(c) Zn15. How would you expect the magnitude of the energy released in the process, 4th shell 1stshell transition, to vary for a He ion compared to a Li 2 ion? Explain your answer. (2)16. Identify the following atoms as either paramagnetic or diamagnetic. (3)(a) Ga(b) Cr(c) Ni5

AP WORKSHEET 01g: Photoelectron Spectroscopy1. Consider the simulated PES plot shown below, that is produced by the analysis of the atoms of aRelative number of electronssingle element. All peaks in the PES are shown.62115012.17.81.1 0.58EnergyIncreasing(a) Using the plot, suggest the electron configuration of the element and hence identify the element.(2)(b) Which two peaks are likely to represent electrons that are most likely to be removed whenthese atoms form ions? Explain. (3)(c)Using your answer in (b), identify the mostly likely charge on an ion of this element. Explain (2)(d) Suggest a reason for the huge jump in energy between the peak at 12.1 and the peak at 150. (2)(e) Suggest a reason for the x-axis being labeled with increasing values from right to left.1

2. Consider the simulated PES plot shown below, that is produced by the analysis of the atoms of aRelative number of electronssingle element. All peaks in the PES are shown.652127326.8202.4 1.25EnergyIncreasing(a) Write the electron configuration and identify the element. (2)(b) The plot is divided into three separate areas on the x-axis. Why is the axis divided in thismanner? (2)(c)What would be the charge on an ion formed from this atom? Justify your answer. (2)(d) What is the significance of three of the peaks having the same height? (2)(e) The peaks at 1.25 & 2.44, as well as the peaks at 20.2 & 26.8, are relatively close to oneanother but have different energies? Explain why they are of the same magnitude but slightlydifferent. (2)2

3. Consider a PES plot for carbon atoms.(a) How many peaks would you expect in the PES for carbon? Explain. (2)(b) What would be the relative heights of the peaks that you have identified in (a)? Explain youranswer carefully. (2)(c)How would you expect the height of the 2p peak in carbon’s PES to compare to the height of the2p peak in nitrogen’s PES? Explain. (2)3

AP WORKSHEET 01h: Ionization Energy1. Explain each of the following observations.(a) Sodium has a lower first-ionization energy than lithium. (2)(b) Oxygen has a lower first-ionization energy than nitrogen. (2)2. Consider the ionization energy plot shown below. Explain each of the following.(a) There is a general increase in the first ionization energy from sodium to argon. (2)(b) Boron has a lower first ionization energy than beryllium. (2)1

2. continued:(c) The first ionization energy of neon (atomic number 10) is significantly higher than that of argon(atomic number 18) but significantly lower than the first ionization energy of helium (atomicnumber 2), despite all three elements being in the same group. (2)(d) Helium has the highest first ionization of all the elements shown. (2)2

3. Consider the ionization energies of elements X and Y shown below in kJmol-1. X and Y are in thesame period of the periodic table and are adjacent to one another in the 2392000023068115375(a) In which group would one find element X? Explain. (2)(b) Does element X lie to the right or the left of element Y in the periodic table? Explain. (2)(c) Which is the first period on the periodic table that these elements could be in? Explain. (2)(d) Why are the second ionization energies of both elements larger than their respe