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July 29, 2015

July 29, 2015

Posted by **Vanessa** on Tuesday, October 16, 2007 at 5:05pm.

mass of flask with water and stopper = 59.479 g

density of the water = 0.9973 g/cm^3

mass of water = 26.845 g

volume of water = 26.918 cm^3

the flask is then emptied and an unknown substance is added

mass of flask with new liquid and stopper = 23.531 g

density of liquid = 0.46710 g/cm^3

the flask is emptied again and dried

pieces of metal were added

weight of stoppered flask and its metal contents = 152.047 g

then filled with water and mass = 165.541

mass of metal = 13.494

mass of water = 13.494

Is the mass of metal and water suppose to be the same?

Can anyone tell me the volume of the water?

What is the volume of the metal?

What is the density of the volume?

Can you show the work? Thanks.

- Chemistry -
**DrBob222**, Tuesday, October 16, 2007 at 5:36pmHow much of this represents what you have done? That is, are all the numbers supplied by the problem or have you worked to obtain some of them. For example, line 5 gives the volume of the water but third line from bottom asks for the volume of water? Also, I don't understand the last line; i.e., "what is the density of the volume?" That doesn't make sense.

- Chemistry -
**DrBob222**, Tuesday, October 16, 2007 at 6:07pmWhile you're at it, also explain the following:

paragraph 3.

mass of flask with new liquid and stopper = 23.531.

mass of flask and stopper = 32.634 (line 1).

How can the flask weigh less when some liquid had been added to the empty flask???

No, the mass of metal is not 13.494 g but the mass of water is. And mass of metal and mass of water MIGHT be the same in some problem but they aren't in this problem. Mass metal in this problem is

fl + stop + metal = 152.047

fl + stop (empty) = 32.634 (line 1)

The difference is the mass metal.

- Chemistry -
- Chemistry -
**Vanessa**, Tuesday, October 16, 2007 at 6:48pmI meant what is the density of the metal. The last question is reffering to the latest problem with water.. not when it was first stated in the beginning of the problem.

- Chemistry -
**DrBob222**, Tuesday, October 16, 2007 at 8:42pm**I don't know exactly how many problems you have here since you refer in your answer to the latest problem with water. So check this work very carefully for I have assumed this is just one giant problem. I still don't get paragraph 2 where an unknown liquid was added and it weighted LESS than the empty container weighed. How can that be?**

Is the mass of metal and water suppose to be the same?

**No, the mass of the metal and water is not the same. The mass of the water is 13.494 g. The mass of the metal is the difference between the empty flask and stopper subtracted from the flask and stopper and metal and I get 119.493. Check that.**

Can anyone tell me the volume of the water?

**The volume of the water is the mass of the water divided by the density of the water. That is 13.494/0.9973 = ??**

What is the volume of the metal?

**The volume of the metal is the difference between the volume of the flask, stopper, and water (that was 26.918 cc) and the volume of water that was added to fill the flask when it caontained the metal (that is 13.494/0.9973). If I didn't make an error (and it's easy to do with so many numbers) I found 13.530 cc). So then the volume of the metal is the difference of the 26.9 something - the 13.5 something.**

What is the density of the volume?

**With the mass of the metal and the volume of the metal, density = mass/volume. My rough answer was about 8.9 or so. The metals in the Co, Ni, Cu group (that area) have densities in that range.**