The population would decrease, the more predators there are the more food needed for the species .
Iron rusts when in contact with water.
Answer:
a. Approximately 
.
b. Approximately 
.
Explanation:
The unit of concentration "
" is equivalent to "
", which means "moles per liter."
However, the volume of both solutions were given in mililiters 
. Convert these volumes to liters:
.
.
In a solution of volume 
where the concentration of a solute is 
, there would be 
(moles of) formula units of this solute.
Calculate the number of moles of 
formula units in each of the two solutions:
Solution in a.:
.
Solution in b.:
.
What volume of that 
(same as 
) solution would contain that many
For the solution in a.:
.
Convert the unit of that volume to milliliters:
.
Similarly, for the solution in b.:
.
Convert the unit of that volume to milliliters:
.
2C4H10 + 13O2 → 8CO2 + 10H2O Since the equation is balanced, we can set up a proportion: 13 moles of O2 react with 2 moles of C4H10x moles of O2 react with 0.425 moles of C4H10 13 → 2x → 0.425 x = 13 * 0.425 / 2 = 2.7625 <span>2.7625 moles of O2 react with 0.425 moles of C4H10</span>
<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>
