Presenting data in tables

A table is often the most appropriate way to present numerical data in a concise, accurate and structured form. Laboratory reports and project dissertations should contain tables which have been designed to condense and display results in a meaningful way and to aid numerical comparison. The preparation of tables for recording primary data is discussed on p. 67. 

Decide whether you need a table, or whether a graph is more appropriate. Histograms and plotted curves can be used to give a visual impression of the relationships within your data (p. 251). On the other hand, a table gives you the opportunity to make detailed numerical comparisons. 

Always remember that the primary purpose of your table is to communicate information and aiiow appropriate comparison, not simply to put down the results on paper  

Constructinci titles - lake Ccare over titles as it is a common mistake in student practical reports to present laljlos without titles, or to mrsconstmet the trtle. 

Every table must have a brief descriptive title. If several tables are used, number them consecutively so they can be quoted in your text. The titles within a report should be compared with one another, making sure they are logical and consistent and that they describe accurately the numerical data contained within them. 

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Mehta and Sloan (1996b) present data in Table 4.9 for 19-structure H hydrates formers along uni variant four-phase lines. With only three exceptions, the enthalpy of hydrate formation is 79.5 kJ/mol 7%. In each case, methane occupies the 512 and the 435663 cages while the larger guest occupies the 51268 cage. 

Presenting data in tables Hints for solving numerical problems Descriptive statis Choosing and usi Drawing chemica Chemdmetrics Computational chemistry -v ... 

A multiple-point standardization presents a more difficult problem. Consider the data in Table 5.1 for a multiple-point external standardization. What is the best estimate of the relationship between Smeas and Cs It is tempting to treat this data as five separate single-point standardizations, determining k for each standard and reporting the mean value. Despite its simplicity, this is not an appropriate way to treat a multiple-point standardization. 

Figure 9.7 Plot of In [r ] versus In M for the data in Table 9.3. An analysis of the Mark-Houwink coefficients from these data is presented in Example 9.3.

The amount of HEU that becomes avadable for civdian use through the 1990s and into the twenty-first century depends on the number of warheads removed from nuclear arsenals and the amount of HEU in the weapons complex that is already outside of the warheads, ie, materials stockpdes and spent naval reactor fuels. An illustrative example of the potential amounts of weapons-grade materials released from dismanded nuclear weapons is presented in Table 7 (36). Using the data in Table 7, a reduction in the number of warheads in nuclear arsenals of the United States and Russia to 5000 warheads for each country results in a surplus of 1140 t of HEU. This inventory of HEU is equivalent to 205,200 t of natural uranium metal, or approximately 3.5 times the 1993 annual demand for natural uranium equivalent. 

Example 13 Evaluation of Investment Priorities Using Prob-ability Calculations A company is considering investment in one or more of three projects, A, B, and C. We wish to evaluate the investment priorities if the prohahihties of attaining various net present values (NPV) are as listed in the third column of Table 9-11. Equation (9-105) gives the expected value for (NPV),. Hence for project A, (NPV), is computed from the data in Table 9-12 and found to be... 

The aim of the tests was to study tank-wall performance. Nevertheless, a few data on BLEVE effects are presented by Schulz-Forberg et al. (1984). An overpressure of 130 mbar was measured at 80 m from the tank position in one of the tests, and was attributed to combustion. Temperatures and pressures at the moment of tank failure were beyond the superheat limit 345-357 K and 24-39 bar, respectively (see propane data in Table 6.1). Fireball development from one test is presented in a series of photographs. The maximum diameter was approximately 50 m, and duration was approximately 4 seconds. Fragmentation data, to the extent published, are given in Section 6.3. 

Table 14.2 repeats some approximate data presented earlier in Table 1.7 for the acid strengths of representative hydrocarbons and reference compounds. 

This algebraic treatment of units to create pure numbers is also convenient for the unambiguous presentation of data in tables and figures. 

Finally, the data in Table 8-6 show the elution of the lead column. The eluent is H,0. The driving force for the elution in this case is the lack of C10 present to act as an anion in the binding of the ammonium perchlorate salt pair. The D-enantiomer versus L-enantiomer ratio in the elution is slightly greater than 6 1, as expected by the inherent selectivity of the ligand. For this separation system, LiClO is then added back to the eluent and the eluent is sent on as load to the next purification stage. 

The approach to equilibrium in the N204-N02 system is illustrated by the data in Table 12.1 and by Figure 12.2 (p. 325) (time is in arbitrary units). Originally, only N204 is present its pressure is 1.00 atm. Because no N02 is around, its original pressure is zero. As equilibrium is approached, the overall reaction is... 

Sb and Ba are present in the airborne gunshot residue expelled from all of the brands of 0.22 cal ammo. A chemical analysis of the primer. of the Western brand gave a Ba to Sb ratio of 65, whereas the same ratio obtained from the data in Table 11 is 2.6. The authors conjecture that this additional Sb left in the air came from the vaporized bullet Pb which contains a large amt of Sb as a hardening agent... 

Considerable practical importance attaches to the fact that the data in Table 6.11 refer to electrode potentials which are thermodynamically reversible. There are electrode processes which are highly irreversible so that the order of ionic displacement indicated by the electromotive series becomes distorted. One condition under which this situation arises is when the dissolving metal passes into the solution as a complex anion, which dissociates to a very small extent and maintains a very low concentration of metallic cations in the solution. This mechanism explains why copper metal dissolves in potassium cyanide solution with the evolution of hydrogen. The copper in the solution is present almost entirely as cuprocyanide anions [Cu(CN)4]3, the dissociation of which by the process... 

Figure 27 shows the discounted cash flow diagram obtained from Table 8 using the data in Table 7. A net present value of 102,462.21 is obtained at end of 15 years of useful life operation, which shows a profitable investment. Approximate discounted payback period is about eight years. Discounted... 

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