Answer:
31.60% phosphorus
Explanation:
To find the percent by mass, you first calculate the total mass and then the mass of phosphorus, and finally divide phosphorus mass by total.
Phosphorus mass: the molar mass of P is 30.97 g/mol, and since there's 1 mole of P, we just have 30.97 g.
Total mass: we add all the molar masses of the components together.
We have 3 moles of H, so we multiply 3 by 1.008 g/mol = 3.024 g H.
We already calculated the mass of phosphorus: 30.97 g P.
We have 4 moles of O, so we multiply 4 by 16.00 g/mol = 64.00 g O.
The total is then the sum: 3.024 + 30.97 + 64.00 = 97.994 g ≈ 97.99 g
Now, to find the percentage, we take 30.97 g P and divide by 97.99:
30.97/97.99 ≈ 0.3160 ⇒ 31.60% P
Thus, the answer is 31.60% phosphorus.
Hope this helps!
Answer:
d
They do not depend on the amount of substance you have.
Answer:
Explanation:
The original calculation to find the number of moles which is 
can be rearranged to give the equation 
. Therefore the amount of molecules can be found by 
(multiplying by Avogadro's Number)
Answer:
0.725 moles
Explanation:
Use the mole = mass/mr equation to find the moles.
Mole = 14.5/20 (Neon's Mr) = 0.725 Moles
Answer:
Compared to early humans our brains seemed to have increased in size, and part of the cause may be because of things like Climage change, ecology and social competition
Explanation:
