O.k. I am confused. So here is what I did.
Mass of empty flask plus stopper: 37.34g
mass of stoppered flask plus water: 63.67g
Mass of stoppered flask plus liquid:
52.01g
Mass of water:
63.67 - 37.34= 26.33
Volume of Flask(density of H20 at 25*C, 0.9970 g/cm^3:
(37.34g)/(0.9970g/cm^3)=37.45cm^3
Mass of Liquid:
52.01g - 37.34g= 14.67g
Density of Liquid:
(14.67)/(0.9970)=14.72g/cm^3
That was part 1 (density of unknown Liquid) Here comes part 2 density of unknown metal.
Mass of stoppered Flask plus metal:
61.28g
Mass of stoppered Flask + Metal+ Water:
78.19g
Mass of metal:
61.28g - 37.34g= 23.94g
(Note that 37.34 is the mass of the stoppered Flask from before)
Mass of water:
78.19g - 61.28g=16.91g
Volume of water:
(16.91)/ (0.9970)=16.96cm^3
Volume of metal:
???????????
I did the following:
(23.94g)/(0.9970g/cm^3)= 24.01cm^3
then using this answer I need to caculate the Density of the Metal:
(23.94g)/(24.01cm^3)= 0.9970 g/cm^3
But why would the Density for water at 25*C, which was given, be the same as the density of the metal? Shouldn't it be different? So I came to the conclusion that in the end I must be doing something wrong because my answer is like walking around in circles...(The last two caculations), so I either don't really get the concept or I made a mistake from the get go...or I am using the wrong numbers, to calculate certain parts. so, this is were i need your help. I hope it's clearer whemn I show you exactly what I did.
You are getting confused with the numbers.
Go back to square 1.
You were correct before that
mass H2O = 26.33 g.
mass liquid = 14.67 g.
volume of H2O = 26.33/0.9970 = 26.409 cc = volume of the liquid.
so density of liquid = mass/volume =14.67/26.409 = 0.55549 which rounds to 4 significant figures as 0.5555
Your original error was in miscalculating the volume of the liquid. The volume of the liquid is the same as the volume of the water and the volume of water is the mass of water divided by the density of water to give the volume of water.
Mass of empty flask plus stopper: 37.34g
mass of stoppered flask plus water: 63.67g
Mass of stoppered flask plus liquid:
52.01g
Mass of water:
63.67 - 37.34= 26.33
Volume of Flask(density of H20 at 25*C, 0.9970 g/cm^3:
You are ok to here.
(37.34g)/(0.9970g/cm^3)=37.45cm^3
You have used the mass of the EMPTY flask. The volume of the flask is the grams H2O in the flask divided by the density of the water which is 26.33 (your figures from above)/0.9970 (the density of the water at the temperature at which the experiment was conducted) = 26.409 cc = volume of flask.
Mass of Liquid:
52.01g - 37.34g= 14.67g
OK here
Density of Liquid:
(14.67)/(0.9970)=14.72g/cm^3
No, the density of the liquid is the mass of the liquid (14.67 is correct) divided by the volume of the liquid. The volume of the liquid is the same as the volume of the water that was in the flask which is 26.409 cc. That's why you went through the whole process of determining the volume of the flask by weighing the water and using the density of water to calculate the volume of the water which also is the volume of the flask. So,
density of liquid = 14.67/26.409 = 0.55549 g/cc which to 4 significant figures is 0.5555 g/cc.
Let's get the first part straight before tackling the second part. I will let you see what you were doing incorrectly for the first part> then using that knowledge work through the density of the metal. Repost that part if you get stuck. Thanks for showing your work. It makes it easier to catch what is going wrong.
That was part 1 (density of unknown Liquid) Here comes part 2 density of unknown metal.
Mass of stoppered Flask plus metal:
61.28g
Mass of stoppered Flask + Metal+ Water:
78.19g
Mass of metal:
61.28g - 37.34g= 23.94g
(Note that 37.34 is the mass of the stoppered Flask from before)
Mass of water:
78.19g - 61.28g=16.91g
Volume of water:
(16.91)/ (0.9970)=16.96cm^3
Volume of metal:
???????????
I did the following:
(23.94g)/(0.9970g/cm^3)= 24.01cm^3
then using this answer I need to caculate the Density of the Metal:
(23.94g)/(24.01cm^3)= 0.9970 g/cm^3
Based on the information you provided, you have calculated the density of both an unknown liquid and an unknown metal. However, you are questioning the fact that the density of water at 25°C (0.9970 g/cm^3) is the same as the density of the metal.
It is important to note that the density values you obtained are not the actual densities of the liquid and the metal. These values represent the density calculated based on the given masses and volumes.
In calculating the density of the liquid, you used the volume of the flask (37.45cm^3) as the volume of the liquid. This assumption may not be accurate since it does not consider the volume of the stopper. To calculate the true volume of the liquid, you need to subtract the volume of the flask (37.45cm^3) from the volume of the flask plus liquid (52.01g).
Therefore, the corrected volume of the liquid can be calculated as follows:
Volume of liquid = Volume of flask + liquid - Volume of flask
Volume of liquid = 52.01cm^3 - 37.45cm^3 = 14.56cm^3
Now, you can recalculate the density of the liquid:
Density of liquid = Mass of liquid / Volume of liquid
Density of liquid = 14.67g / 14.56cm^3 = 1.0072 g/cm^3 (rounded to four decimal places)
Next, for the density of the metal, you have correctly calculated the volume of the metal using the mass and the density of water. However, it is important to note that the density of the metal is not expected to be the same as the density of water. Different substances have different densities.
To confirm if there was an error in your calculation, you could double-check the mass of the metal obtained and ensure it was measured accurately. Additionally, you could consider if there were any possible errors in the experimental procedure or an assumption made in the calculations.
If you are still unsure about the results, it would be helpful to consult your instructor or refer to the lab manual for further clarification or additional steps in the experiment.
I understand that you are confused about your calculations for the density of the unknown liquid and the unknown metal. I will explain the process and help you identify any mistakes.
Let's start with the density of the unknown liquid. You correctly calculated the mass of the liquid as 14.67g and used the formula: Density = Mass/Volume. However, there seems to be a mistake in your calculation. You used the mass of the liquid (14.67g) divided by the density of water (0.9970g/cm^3), instead of dividing it by the volume of the liquid. To calculate the volume of the liquid, you need to use the formula: Volume = Mass/Density. So the correct calculation should be:
Volume of liquid = 14.67g/0.9970g/cm^3 = 14.73cm^3.
Now let's move on to the density of the unknown metal. You correctly calculated the mass of the metal as 23.94g. However, there seems to be a misunderstanding in your calculation of the volume of the metal. You used the same formula as before: Volume = Mass/Density. However, the density you used was the density of water (0.9970g/cm^3) instead of the density of the metal. To calculate the volume of the metal, you need to rearrange the formula to: Volume = Mass/Density. The correct calculation should be:
Volume of metal = 23.94g/Density of metal.
Now, to find the density of the metal, divide the mass of the metal by its volume: Density of metal = Mass of metal/Volume of metal.
It is important to note that the density of the metal should not be the same as the density of water. Each substance has its own unique density, so the two values should not be equal.
To correct your calculations, you need to find the actual density of the metal by using its correct volume value. If you have the volume of the metal given in the problem or if you can find it using a different method, you can substitute that value into the formula to calculate the correct density.
I hope this clarifies your confusion and helps you understand the concept better. If you have any further questions or concerns, please let me know.