Chemistry/ Biotechnology Reference Sheets

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1 Cmmn Metric Prefixes: Giga (G) = 1,000,000,000 = Kil (k) = 1,000 = Deci (d) =.1 = Milli (m) =.001 = Nan (n) = = Mega (M) = 1,000,000 = Basic unit = meter, gram, liter, secnd = Centi (c) =.01 = Micr ( ) = = Cmmn Metric-English Apprximate Equivalents: Length: 1 inch (in) = 2.54 centimeters (cm) Vlume: 1 quart (qt) = 946 milliliters (ml) Mass: 1 pund (lb) = 454 grams (g) ime: 1 secnd (sec) = 1.00 secnd (s) Metric System Exact Equivalents: Length: 1 meter (m) = 100 centimeters (cm) Mass: 1 gram (g) = 1000 milligrams (mg) 1 meter (m) = 1000 millimeters (mm) 1 kilgram (kg) = 1000 grams (g) 1 kilmeter (km) = 1000 meters (m) 1 metric tn (m tn) = 1000 kilgrams (kg) Vlume: 1 Liter (L) = 1000 milliliters (ml) 1 Liter (L) = 10 deciliters (dl) 1 milliliter (ml) = 1 cubic centimeter ( cm ) English System Exact Equivalents Length: 1 ft (ft) =12 inches (in) Vlume: 1 quart (qt) = 2 fluid unces (fl z) 1 mile (mi) = 1760 yards (yd) 1 quart (qt) = 2 pints (pt) 1 mile (mi) = 5280 feet (ft) 1 galln (gal) = 4 quarts (qt) Mass: 1 pund (lb) = 16 unces (z) 1 tn = 2000 punds (lb)

2 Significant Figures in Chemistry Exact Values = Unlimited Significant Figures (SF s apply nly t measurements) Measurements (Cunt the number f digits frm left t right): A) Start with the first nn-zer digit. B) D nt cunt place hlder zers (0.011, , and 11,000 each have nly tw significant digits) Significant Figures in Calculatins in Chemistry Additin/ Subtractin: he answer is limited t the least certain measurement in a set f data. Multiplicatin/ Divisin: he answer is limited t the least number f significant digits in the given data. emperature Equivalents 9 ( ) 2 ( C F ) 5 5 ( 2) ( F C ) 9 ( C) 27 K Energy Equalities 1 calrie (cal) = jules (J) 1 kilcalrie (kcal) = 1000 calries (cal) = 1 fd Calrie (Cal) 1 kilcalrie (kcal) = kiljules (kj) Specific Heat Equatin q mc q=heat in calries m=mass in grams c=specific heat in [cal/(grams degrees Celsius)] = change in temperature in degrees Celsius Weighted Percentage Calculatins Atmic Mass = (Mass f Istpe#1 X Abundance Percentage) + (Mass f Istpe#2 X Abundance Percentage) Calculatin f Number f Prtns and Neutrns fr an Element Atmic Mass = ttal prtns + ttal neutrns (tal Prtns = Atmic Number)

3 1 Ml = mlar mass f a substance = Mlarity= mles/liter f slutin. Stichimetry Analysis Strategy 2 C( s) O ( g) 2 CO( g) Cnversin Factrs: 2 2 2mlC 1mlO, 2mlC 2mlCO, 1mlO2 2mlCO X10 atms = 22.4L at SP Byles Law: Charles Law: Cmbined Gas Law: 1 2 V V where needs t be represented in Degrees Kelvin Standard Cnditins f emperature and Pressure fr gasses: emp. = 0 C = 27 K Press. = 1 atmsphere= 760 mm Hg = 760 trr = 76 cm Hg Direct Prprtins: Values n ne side f the equals sign increases causes the ther side f the equals sign t increase. Values n ne side f the equals sign decreases causes the ther side f the equals sign t decrease. Indirect Prprtins: Values n ne side f the equals sign increases causes the ther side f the equals sign t decrease. Cncentratin Frmula: M V M V where MV are the Mlarity and Vlume f the initial cncentrated slutin and MV are the Mlarity and Vlume f the final diluted slutin.

4 Stck Slutin Frmula: CV C V where CV are the Cncentratin and Vlume f the initial cncentrated slutin and CV are the Cncentratin and Vlume f the final diluted slutin. (Initial cncentratin wuld als be knwn as the Stck Slutin.) Using he CV C V Equatin: Step 1) Determine the initial cncentratin f stck slutin. his is C1. Step 2) Determine the vlume f stck slutin required. his is usually the unknwn. Step ) Determine the final cncentratin required. his is C2. Step 4) Determine the final vlume required. his is V2. Step 5) Insert the values determined in steps 1-4 int the frmula and slve fr the unknwn. Nte: his equatin is nly used when calculating hw t prepare a less cncentrated slutin frm a mre cncentrated slutin. D nt use this equatin in ther situatins. Equilibrium Cnstant (K): c d [ C] [ D] K, where C and D are the cncentratins f the prducts, A and B are the cncentratins a b [ A] [ B] f the reactants, a and b are the stichimetric cefficients f the prducts, and c and d are the stichimetric cefficients f the reactants. ph Calculatins: ph lg[ H O ], where a ph<7 is acidic, a ph>7 is basic, and a ph=7 is neutral. Graphing Bacterial Grwth: When graphing using semilg paper, use the y-axis t represent the lg f the number f cells present and the x-axis as the time elapsed. (Make sure that the scale is cnsistent between each f the divisins n each f the axes) Rules Fr Manipulating Percents: 1. cnvert a percent t its decimal equivalent mve the decimal pint tw places t the left. 2. change a decimal t a percent, mve the decimal pint tw places t the right and add a % sign.

5 . change a percent t a fractin, write the percent as a fractin with a denminatr f cnvert a fractin t a percent, cnvert the fractin t its decimal equivalent and then mve the decimal tw places t the right and add a % sign. 5. find a percentage f a particular number cnvert the percent t its decimal equivalent and multiply the decimal times the number f interest. Percent Errr: Percent Errr=[ (rue Value Average Measured Value) X 100%]/(rue Value) Cncentratin: he amunt f a particular substance (slute) in a stated vlume (r mass) f a slutin r mixture. (Cncentratin is the rati where the numeratr is the amunt f the material f interest and the denminatr is usually the vlume r smetimes mass f the entire mixture.) Calculating the Cncentratin f Slute After Diluting a Stck Slutin: Rule 1: calculate the cncentratin f a substance in a diluted sample, multiply the riginal cncentratin f the substance times the dilutin. Rule 2: calculate the cncentratin f a substance in an riginal stck slutin, multiply the cncentratin f the substance in a diluted sample times the inverse f the dilutin (expressed as a fractin).