I am doing a lab on finding the molecular mass of a volatile liquid.
I first need to find the volume of water in the test tube. (V= m/d)
... but how do I find the density of the water in the first place to use it in the equation?
(I am not given the volume (it's what i'm trying to find)
-- all i have is the mass of the water
I'm so lost right now.
Thanks for the help!!!
you have to know that the density of water is 1g/mL
The density of water of 1.00 g/mL is a relatively safe number to use. If you are running an extremely accurate assessment for the molecular mass, you read the temperature of the water with a thermometer and look up the density of water in a set of tables corresponding to that temperature. Here is a site that gives density versus temperature up to about 30 C or so.
To find the density of the water, you will need to use a known volume of water and its corresponding mass. Here's how you can do it:
1. Obtain a sample of water with a known volume, such as 10 mL or any convenient volume. This can be measured using a graduated cylinder or any other measuring device.
2. Measure the mass of the water sample using a balance. Make sure the balance is properly calibrated before taking the measurement.
3. Now, you can calculate the density of water using the formula: density (d) = mass (m) / volume (V)
For example, if the mass of the water sample is 10 grams and the volume is 10 mL, the density would be: density = 10 g / 10 mL = 1 g/mL.
4. Once you have the density value, you can use it in your original equation to find the volume of water in the test tube. Remember, the equation is V = m / d, where m is the mass of the water and d is the density.
For example, if you have the mass of the water as 5 grams and the density you calculated earlier is 1 g/mL, you can calculate the volume using the equation: V = 5 g / 1 g/mL = 5 mL.
So, by using a known volume of water and its corresponding mass, you can determine the density of the water, which can then be used to find the volume of the water in the test tube.