In france grapes are 1.83 euros per kilogram. What is the cost of grapes in dollars per pound if the exchange rate is 1.40 dollars per euro
1.83 euros x 1.40 = 2.56 dollars
1 pound = 0.454 kilogram
1.83 euros per kilogram = 2.56 x 0.454 = 1.16 dollars per pound
Atomic mass Calcium = 40.078 a.m.u
40.078 g ---------------- 6.02x10²³ atoms
165 g -------------------- ??
165 x ( 6.02x10²³) / 40.078 => 2.47x10²⁴ atoms
hope this helps!
<span>Well it depends on percentage by what, but I'll just assume that it's percentage by mass.
For this, we look at the atomic masses of the elements present in the compound.
Cu has an atomic mass of 63.546 amu
Fe has 55.845 amu
and S has 36.065 amu
Since there are 2 molecules of Sulfur for each one of Cu and Fe, we'll multiply the Sulfur atomic weight by 2 to obtain 72.13 amu
So we have not established the mass of the compound in amus
63.546 + 55.845 + 72.13 = 191.521
That is the atomic mass of Chalcopyrite. and Iron's atomic mass is 55.845
So to get the percentage, or fraction of iron, we take 55.845 / 191.521
Which comes out to 29.15% by mass
Mass of the sample is not needed for this calculation, but since the question mentions it I would go ahead and check if the question isn't also asking for the mass of Iron in the sample as well, in which case you just find the 29.15% of 67.7g</span>
Division (asexual) method, and the sexual method of reproduction where two organisms produce an offspring. The sexual reproduction requires the interaction of two organisms; gametes, typically a fertilization. The offspring consists of characteristics derived from both of the parental organisms.
<span>Displaced volume :
final volume - initial volume
32.4 mL - 25.2 mL => 7.2 mL
Density = mass / volume
D = 22.6 g / 7.2 mL
D = 3.1388 g/mL
hope this helps!</span>
