Introduction to Laboratory Glassware and Measurement (1)

Introduction to Laboratory Glassware and Measurement Makayla Pearson Section #012 Part A: Determination of water density using different glassware. Table 1: Density determination of water with different glassware Glassware Trial Volume of water (mL) Mass of water (g) Density (g/mL) Mean Density (g/mL) Standard Deviation (g/mL) Percent (%) Error (g/mL) Graduated Cylinder 1 2 3 49.00 mL 49.00 mL 49.00 mL 47.93 g 48.16 g 48.35 g 0.98 g/mL 0.98 g/mL 0.95 g/mL 0.97 g/mL 0.017 g/mL 2.827% Beaker 1 2 3 50.00 mL 50.00 mL 50.00 mL 23.96 g 24.44 g 25.27 g 0.48 g/mL 0.49 g/mL 0.51 g/mL 0.49 g/mL 0.015 g/mL 50.91% Erlenmeyer flask 1 2 3 50.00 mL 50.00 mL 50.00 mL 40.08 g 41.43 g 42.04 g 0.82 g/mL 0.83 g/mL 0.84 g/mL 0.82 g/mL 0.01 g/mL 17.85% Volumetric flask 1 2 3 50.00 mL 50.00 mL 50.00 mL 49.66 g 49.72 g 49.75 g 0.99 g/mL 0.99 g/mL 0.99 g/mL 0.99 g/mL 0 g/mL 0% Calculations :  Density (m/v) o Graduated Cylinder  47.93 g/49.00 mL  = 0.968163265 g/mL  ≈ 0.97 g/mL o Beaker  23.96 g/50.00 mL  = 0.4792 g/mL  ≈ 0.48 g/mL o Erlenmeyer Flask  40.80 g/50.00 mL  = 0.816 g/mL  ≈ 0.82 g/mL o Volumetric Flask  49.66 g /50.00 mL  = 0.9932 g/mL  ≈ 0.99 g/mL

 Mean Density - (Σm/ Σv) o Graduated Cylinder  Σ 144.55 g / Σ 147 mL  = 0.98333 g/mL  ≈ 0.98 g/mL o Beaker  Σ 73.67 g/ Σ 150 mL  = 0.491133333 g/mL  ≈ 0.49 g/mL o Erlenmeyer Flask  Σ 123.55 g / Σ 150 mL  = 0.82366667 g/mL  ≈ 0.82 g/mL o Volumetric Flask  Σ 149.13 g/ 150 mL  =0.9942 g/mL  ≈ 0.99 g/mL  Standard Deviation σ = √(∑(x−¯x) ( x − x ¯ ) 2 /n)) o Graduated Cylinder o 0.0006 g/mL ÷ 2 g/mL o = 0.0003 g/mL o √0.0003 g/mL o = 0.017320508075689 g/mL o ≈ 0.017 g/mL o Beaker o 0.00046666666666667 g/mL ÷ 2 g/mL o = 0.00023333333333333 g/mL o √0.00023333333333333 g/mL o 0.015275252316519 g/mL o ≈ 0.015 g/mL o Erlenmeyer Flask o 0.0002 g/ml ÷ 2 g/mL o = 0.0001 g/mL o √0.0001 g/mL o = 0.01 g/mL o Volumetric Flask o 3.6977854932235E-32 g/ mL ÷ 2 o = 1.8488927466117E-32 o √1.8488927466117E-32