Significant figures final zeros

One or more final zeros placed to the right of the decimal point may be considered to be significant. For example, 2.0050 has 5 significant figures. 

One or more final zeros (zeros that end the measurement) used after the decimal point are significant. So 1.760 has four significant figures, and 1.7600 has five significant figures. The number 0.0001200 has only four significant figures because the first zeros are not final. 

Final zeros after the decimal point are significant figures and are used to indicate the decimal place to which the measurements are reliable. Thus 1.0 cm indicates a length reliably known to tenths of a centimeter but not to hundredths of a centimeter, whereas 1.000 cm indicates a length reliably known to thousandths of a centimeter. A very common mistake is leaving out these zeros when the measured quantity has an integral value. 

Final zeros are significant if a decimal is present. For example, 200. and 2,500. have three and four significant figures, respectively. 

Final zeros located after a decimal are significant. For example, the numbers 2.50 and 3.7770 have three and five significant figures, respectively. 

Table 8.4. State multipoles at Eo=350 eV, 6=3° for the n=2 excitation of hydrogen using positive, negative and zero electric fields. The experimental data are due to Williams and Heck (1988). Errors in the final significant figures are given in parentheses. Calculations are CCO, method of Bray, Madison and McCarthy (1990) and vWW, van Wyngaarden and Walters (1986)...

If you have a number such as 0.003 67, then it will not be possible to give an answer to 2 decimal places, as the final answer would be zero - not a sensible answer. Always try to look at the answer you have from a commonsense point of view and don t just write down the answer the calculator gives you. In any exam requiring calculation, you will invariably lose a mark by writing an answer that gives an absurd number of significant figures. .. 

Note In these problems, the final zeros given in temperatures and pressures (for example, 20°C, 760 mmHg) are significant figures. 

Round off or add zeros to the following calculated answers to give a final answer with three significant figures (2.2)... 

All final zeros to the right of the decimal place are significant. 6.00 g has three significant figures... 

Figure 23 A proposal for dephasing in ethanol by solvent-assisted intramolecular vibrational redistribution (IVR). The yym-methyl stretch is initially excited, but rapidly equilibrates with one or more modes within kT (the ayym-methyl stretch and/or CH bend overtones). Dephasing occurs with this rapid equilibration time Tivr- However, significant population remains in the sym-methyl stretch after equilibration. Relaxation from this group of state to lower states causes the final relaxation of the population to zero, which is measured as Tj in energy relaxation experiments. (Adapted from Ref. 7.)...

Fig. 7. The final set of mechanisms produced here and their correspondence to the mechanisms constructed by Happel et al. (1990). As was explained earlier, the intermediate 7 does not need to be eliminated because its column contains only zeros. All the direct mechanisms identified by Happel el at. (1990) have been produced. However, the last three mechanisms in Figure 7 are actually identical. Hence, the simple procedure discussed here does not preclude multiple occurrences of the same mechanism, or, as the next example will show, the occurrence of mechanisms that are not direct. For small studies this is not a significant drawback, because one can easily eliminate the redundancies in the end. The potential duplication of mechanisms and construction of indirect mechanisms are addressed by Mavrovouniotis (1992). [Reprinted with permission from Mavrovouniotis, M. L., and Stephanopoulos, G. Synthesis of reaction mechanisms consisting of reversible and irreversible steps I. A synthesis approach in the context of simple examples . Ind. Eng. Chem. Res. 31, 1625-16.37, (1992). Copyright 1992 American Chemical Society.]...

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