We calculated the mass of the water after adding water in increments of 10mL until we got a total of 30 mL. These are the measurements I recorded...
cylinder empty- 87.470g
with 10mL of water- 97.470g
with total of 20 mLof water- 107.470g
with total of 30 mL of water- 117.470g
1. You have taken measurements of three volumes of water. Record the following masses for each of the three measurements (in grams):
(a) mass of the graduated cylinder alone: 87.470 g
(b) mass of the graduated cylinder plus the water inside: 117.470 g
(c) net mass of the water: 30.000 g
2. For each of the three measurements, record and calculate the following. Note that a cubic centimeter (cm³) is equivalent to a milliliter (mL).
(a) total volume of water (in mL or cm³): 30 mL
(b) total mass of water (in grams): 117.470 g (is this right?)
(c) density of the water (in grams/cm³): 3.9156 mL. I did this by saying 117.470/30
3. Calculate the average of the three density measurements for water.
Part 3, is where I'm having trouble with.
I simply added the three weights of the water and divided by three to get 107.47. Are these answers correct??
cylinder empty- 87.470g
with 10mL of water- 97.470g
with total of 20 mLof water- 107.470g
with total of 30 mL of water- 117.470g
1. You have taken measurements of three volumes of water. Record the following masses for each of the three measurements (in grams):
(a) mass of the graduated cylinder alone: 87.470 g
(b) mass of the graduated cylinder plus the water inside: 117.470 g
(c) net mass of the water: 30.000 g
2. For each of the three measurements, record and calculate the following. Note that a cubic centimeter (cm³) is equivalent to a milliliter (mL).
(a) total volume of water (in mL or cm³): 30 mL
(b) total mass of water (in grams): 117.470 g (is this right?)
(c) density of the water (in grams/cm³): 3.9156 mL. I did this by saying 117.470/30
3. Calculate the average of the three density measurements for water.
Part 3, is where I'm having trouble with.
I simply added the three weights of the water and divided by three to get 107.47. Are these answers correct??
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2
(b) Mw = M - Mc = 117.47 - 87.47 = 30 g (for the last measurement only)
(c) ρ = m/v = 30/30 = 1.00 g/ml
3. Each of your 3 measurements will yield 1.00 g/ml because they each show the water mass in grams to be the same number as the water volume in ml. When measuring the mass of anything, you always have to subtract the mass of the container from the reading on the balance.
ρav = (1.00 + 1.00 + 1.00)/3 = 1.00 g/ml
(b) Mw = M - Mc = 117.47 - 87.47 = 30 g (for the last measurement only)
(c) ρ = m/v = 30/30 = 1.00 g/ml
3. Each of your 3 measurements will yield 1.00 g/ml because they each show the water mass in grams to be the same number as the water volume in ml. When measuring the mass of anything, you always have to subtract the mass of the container from the reading on the balance.
ρav = (1.00 + 1.00 + 1.00)/3 = 1.00 g/ml