N = given mass/ molar mass.
n = number of moles
given mass = 2.47 g
molar mass = 197 g/mol
n = 2.47 / 197
n = 0.01253 moles.
I'm sure you wanted to ask more than this. Just put some comments in. I can do the same.
Given the mass of Titanium = 3.8 lb
Density of Titanium is 4.506 
We can calculate the volume of Titanium using density and mass.
Converting mass from lb to g:

Calculating the volume of Titanium using density and mass:

Converting volume from
:

Answer:
The molecular formula is C2H2Br4
Explanation:
Molar Mass of CHBr2 = 12 + 1 + (2x80) = 12 + 1 + 160 = 173
The molecular formula = n x empirical formula
Molar Mass of the compound = 345.6
Empirical formula = CHBr2
n(CHBr2) = 345.6
n x 173 = 345.6
n = 345.6/173 = 2
Therefore the molecular formula is n(CHBr2) = 2(CHBr2) = C2H2Br4
Answer:
selective breeding
Explanation:
Example: pretend that rabbits can only be brown or black and black is dominant. If only the brown rabbits reproduce it will eventually be more common Hope this helps
We must first find the molar weight of Tungsten, found on the periodic table as 183.84g per mole.
We are told to find the mass of a sample containing 0.700 moles of Tungsten, so we can set this up in a multiplication equation and cancel units to find the mass in grams:

So the answer that is closest to this value is
C) 129g.