The answer is Velocity and potential energy. Kinetic energy is the total energy of a system or an object in motion and requires movement.
<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>
The answer is c. unchanged........
The answer
first of all, we should know that NaOH is a strong base. For such a product, the conentration of the OH - is equivalent to the concentration of the NaOH itself.
that means:
[ OH -] = [ NaOH] =<span>0.001 62
and for a strong basis, pH can be calculated as pH = 14 + log </span>[ OH -]
first we compute log [ OH -] :
log [ OH -] = log (0.001 62)= -2.79
finally pH = 14 -2.79 = 11.20
75.7 grams.
Convert moles to grams using this:
Moles • grams/1 mole = grams
(Grams is over 1 mole)
