Question

Data 1A: (Please fill out this table and submit with the lab report. Recopy if messy)

For each piece of glassware, calculate the mass of the water added, then use the density of water (0.998 g/mL) to find the calculated volume of the water. Record your three volume calculations below. Be sure to that all measurement include the correct number of significant figures and appropriate units.

	100 mL beaker	10 mL grad. cyl.	100/50 mL grad. cyl.
Dry Mass	59.548g	38.640g	87.003g
Dry Mass of container + H2O	72.199g	48.548g	95.905g
Mass of H2O (subtract the masses)	12.651g	9.908g	8.902g
CalculatedVolume (from mass of H2O)	12.676mL	9.926mL	8.920mL

Sample Calculations: (Show a sample of each type of calculation you did)

Mass of H₂O = (Dry mass of container + H₂O) – (Dry mass)

72.199g – 59.548g = 12.7g

            Volume = mass of H₂O / Density of Water

12.651g/ 0.998g/mL =12.7mL
Data 1B: (Please fill out this table and submit with the lab report. Recopy if messy)

	Metal A	Metal B	Metal C	Metal D	Metal E
Mass of metal(g)	17.077mL	5.417g	22.704g	15.174g	13.655g
Initial Volume of Water	10.1mL	10.3mL	10.5mL	9.9mL	11.2mL
Volume of water + metal (mL)	12.2mL	12.1mL	12.3mL	11.8mL	12.3mL
Volume of metal (mL) (subract volumes)	2.2mL	1.8mL	1.8mL	1.9mL	2.1mL
Density of metal (g/mL)	8.9g/mL	3.0g/mL	13g/mL	8.0g/mL	6.5g/mL
Identity of metal	Cu	Al	Pb	Fe	Zn

Sample Calculations: (Show a sample of each type of calculation you did)

Calculations

1. Volume of Metal = (volume of water + metal) – (initial volume of water)

                                    12.2mL – 10.1mL = 2.1mL

2. Density of Metal = mass of metal / volume of metal

                                    17.077g / 2.1Ml =8.1g/mL

Need help with the question below

Determination of percent error (for glassware and metal densities)

Typed discussion of measured results vs literature results and description of possible sources of error. Note that “human error” is not an acceptable answer. Please be specific.

Answer 1

Calculated Density of Metal A = 17.077 / 2.1 = 8.1 g/mL

Observed density of metal A = 8.9 g/mL

% error in density of metal A = 8.9 - 8.1 / 8.9 * 100 = 8.98%

% error in density of metal B = (3.01 - 3 / 3) * 100 = 0.3%

% error in density of metal C = ( 13 - 12.61 / 13 ) * 100 = 2.97%

& error in density of metal D = ( 8 - 7.99 / 8 ) * 100 = 0.125%

% error in density of metal E = ( 6.502 - 6.5 / 6.5 ) * 100 = 0.03 %

So,

Metal A - Measured Density = 8.9 g/mL and Observed density = 8.1 g/mL

Metal B - Measured Density = 3 g/mL and Observed density = 3.01 g/mL

Metal C - Measured density = 12.61 g/mL and Observed density = 13 g/mL

Metal D - Measured Density = 7.99 g/mL and Observed density = 8.00 g/mL

Metal E - Measured density = 6.502 g/mL and Observed density = 6.5 g/mL

Sources of error

Error in weight balance is possible if it is not zeroed

Incorrect measurement of volume due to defects in glassware