Answer:
1.13×10^25 molecules of water.
Explanation:
Equation of the reaction;
C8H18(g) + 25/2 O2 (g) -------> 8CO2(g) + 9H2O(l)
It is important to first put down the balanced reaction equation. It is not possible to solve any problem on stoichiometric relationship without a balanced reaction equation. Once the equation is obtained, we can now proceed with other steps in the solution of the problem.
From the reaction equation, 1 mole of C8H18 produces 9 moles of water
1 mole of C8H18 occupies 22.4L volume while 1 mole of water contains 6.02×10^23 molecules of water
Hence
22.4 L of C8H18 produces 9(6.02×10^23) molecules of water
46.72 L of C8H18 will produce 46.72 L × 9(6.02×10^23) molecules of water/22.4 L
= 113×10^23 or 1.13×10^25 molecules of water.
<span>(6.36x10^25)/(6.02*10^23) is approximately 105.6 moles</span>
Answer C
I could be wrong
Explanation
Answer is: <span>c. Fe</span>₃<span>O</span>₄<span>.
</span>ω(Fe) = 72,360%.
ω(O) = 100% - 72,36% = 27,64%.
For example, if we the mass of compound is 100 g:
m(Fe) = 72,36 g.
n(Fe) = m(Fe) ÷ M(Fe).
n(Fe) = 72,36 g ÷ 55,85 g/mol.
n(Fe) = 1,296 mol.
n(O) = 27,64 g ÷ 16 g/mol.
n(O) = 1,727 mol.
n(Fe) : n(O) = 1,296 mol : 1,727 mol.
n(Fe) : n(O) = 1 : 1,33 or 3 : 4.