The mass, in grams, of the sample of methanol (CH₃OH) is 64 grams.
<h3>How we calculate mass from moles?</h3>
Mass of any substance can be calculated by using moles as:
n = W/M, where
W = required mass
M = molar mass
In the question that:
Moles of methanol = 2mole
Molar mass of methanol = 32g/mole
On putting these values in the above equation, we get
W = n × M
W = 2mole × 32g/mole = 64g
Hence, 64 grams is the mass of the sample.
To know more about moles, visit the below link:
brainly.com/question/15374113
A is obviously out because it leads to a volume of 125.0 milliliters of the new solution and gives you a lower concentration than you were aiming for.
D is out because you are adding 75 milliliters of the stock solution, so your concentration would be too high. You only need 25.0 milometers of stock solution per 100 milliliters of the new solution.
C is also out because it leads to 50.0 milliliters stock solution per 100 milliliters of the new solution and hence the wrong concentration.
B is by default the correct answer. It also details the correct technique. First you add the stock solution (This you know from your calculations to be 25 milliliters.) then you add the water up to the volume you needed. (Because the calculations only tell you the total volume of water not what you need to add) You also add the water last so you can rinse the neck of the flask to make sure you also get all the stock solution residue into the stock solution.
I would add the final step of stirring, but B is the only answer that can be correct.
Sorting is a method that could separate those materials
The speed at which seismic waves travel depends on the properties of the material that they are passing through. For example, the denser a material is, the faster a seismic wave travels. P waves can travel through liquid and solids and gases, while S waves only travel through solids.
Melamine should be the right answer, i hope this helps.
