Answer:- C. Hafnium.
Solution:- Mass of the sample is 46.0 g and it's volume is .
From mass and volume, we can calculate it's density using the formula:
On the basis of the density, this substance could either be mercury or hafnium. Since the substance is a solid at room temperature where as mercury is liquid. So, it can't be mercury.
The right choice is C) Hafnium.
Chlorine. i think it has one less electron.... i'm not sure though.
Given mass of solute = 340 gram
Molar mass of solute(MgBr2) = 184 g
Number of moles = Given mass / Molar mass = 340 / 184 = 1.85 moles
Now, Molarity = Number of moles / solution (in litres)
So, M = 1.85 / 8
M = 0.23 M
In short, Your Molarity would be: 0.23 M
Hope this helps!
Answer:
I think is the last one.
Anthracite – Stage Four
Anthracite, the fourth stage in coal formation, is also known as “hard coal” because it is hard and has a high lustre. It appears to have been formed as a result of combined pressure and high temperature. Anthracite burns with a short flame and little smoke.