A. The mass of one mole of the virus is calculated by multiplying the mass of a single virus by the Avogadro's number which is equal to 6.022 x 10^23. Performing this operation,
mass = (9.0 x 10^-12 mg)(6.022 x 10^23) = 5.42 x 10^12 mg
In correct number of significant figures, the answer would only have to be 5.4 x 10^12 mg.
b. The number of moles of the virus that will have the same mass as the oil tanker is calculated by dividing the mass of the oil tanker by the mass of one mole of the virus. Note that doing division, both would have to have the same units.
n = (3.0 x 10^7 kg) / (5.4 x 10^12 mg)(1 g/1000 mg)(1 kg/1000 g)
Simplifying,
n = 6
In correct number of significant figures, the answer is 6.0.
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Answer:
Given the following list of densities, which materials would float in a molten vat of lead provided that they do not themselves melt?
Densities (g/mL): lead = 11.4, glass = 2.6, gold = 19.3, charcoal = 0.57, platinum = 21.4.
glass and charcoal
Explanation:
The density of molten lead is about 10.65Kg/m^3
By Archimedes principles, the buoyancy of an object in a fluid is proportional to the mass of fluid displaced
which in turn is proportional to the object's density
Generally an object well float when placed on a denser medium
glass =2.6, and charcoal =0.57 are both less dense so they will float on Lead
Answer:

Explanation:
Using the Ideal Gas Law we have
and the number of moles n could be expressed as
, where m is the mass and M is the molar mass.
Now, replacing the number of moles in the equation for the ideal gass law:

If we pass the V to divide:

As the density is expressed as
, we have:

Solving for the density:

Then we need to convert the units to the S.I.:






Finally we replace the values:



