SG and Mass Ratio

[drillers]

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The SG of Mercury is 13.6, what will be the mass ratio of a very tall column of mercury compared to a column of water that is the same height?
(water has a higher bulk modulus than mercury)
a. 13.6
b. less than 13.6
c. more than 13.6
d. 1

I thought that the mass ratio of mercury to water would be 13.6 since they have the same height and the SG of mercury is 13.6x greater than water's

C is the correct answer, and I am not really understanding how the Bulk Modulus changes things

 

[benjaminl1nus]

OK. So right off the bat, you know mercury is 13.6 times denser than water. Now, since the question says that water has a higher bulk modulus than mercury (this basically means that water's volume in the column is incompressible, and also that mercury can compress more in a column relative to normal), so since mercury can pack more densely in a column then its mass ratio should be more than 13.6. make sense??

 

[pm1]

OK. So right off the bat, you know mercury is 13.6 times denser than water. Now, since the question says that water has a higher bulk modulus than mercury (this basically means that water's volume in the column is incompressible, and also that mercury can compress more in a column relative to normal), so since mercury can pack more densely in a column then its mass ratio should be more than 13.6. make sense??

is this because volume of mercury will be smaller?

 

[drillers]

OK. So right off the bat, you know mercury is 13.6 times denser than water. Now, since the question says that water has a higher bulk modulus than mercury (this basically means that water's volume in the column is incompressible, and also that mercury can compress more in a column relative to normal), so since mercury can pack more densely in a column then its mass ratio should be more than 13.6. make sense??

Yeah I think that makes sense...

when a substance has a greater modulus, that means that the stretching/comrpessing (any type of change) is going to be smaller. So since water has the higher modulus than mercury --> mercury has the smaller modulus and can compress more and is thus more dense so the mass ratio of mercury to water will be greater than 13.6