Answer:
0.267 mol
Explanation:
The <em>unbalanced equation</em> for the reaction that takes place is:
Once we balance it we're left with:
- 2C₈H₁₈ + 25O₂ → 18H₂O + 16CO₂
Using the <em>stoichiometric ratio </em>of water and octane from the balanced reaction, we can <u>convert mol of water into mol of octane</u>:
- 2.40 mol H₂O *
= 0.267 mol C₈H₁₈
Thus 0.267 moles of octane are needed to produce 2.40 mol of water.
Answer:
a) MZ₂
b) They have the same concentration
c) 4x10⁻⁴ mol/L
Explanation:
a) The solubility (S) is the concentration of the salt that will be dissociated and form the ions in the solution, the solubility product constant (Kps) is the multiplication of the concentration of the ions elevated at their coefficients. The concentration of the ions depends on the stoichiometry and will be equivalent to S.
The salts solubilization reactions and their Kps values are:
MA(s) ⇄ M⁺²(aq) + A⁻²(aq) Kps = S*S = S²
MZ₂(aq) ⇄ M⁺²(aq) + 2Z⁻(aq) Kps = S*S² = S³
Thus, the Kps of MZ₂ has a larger value.
b) A saturated solution is a solution that has the maximum amount of salt dissolved, so, the concentration dissolved is solubility. As we can notice from the reactions, the concentration of M⁺² is the same for both salts.
c) The equilibrium will be not modified because the salts have the same solubility. So, let's suppose that the volume of each one is 1 L, so the number of moles of the cation in each one is 4x10⁻⁴ mol. The total number of moles is 8x10⁻⁴ mol, and the concentration is:
8x10⁻⁴ mol/2 L = 4x10⁻⁴ mol/L.
The molar mass of CO2 is 44 grams per mole.
165 grams / 44 grams per mole of CO2 = 3.75 moles CO2
Using Avogadro’s law where 1 mole of substance equals
6.023 x 10^23 molecules
3.75 moles CO2 (6.023 x 10^23 molecules /mole) = 2.26 x 10^24 molecules CO2
12. B
13. B
14.D
15. A.
16.C.
17. C
18.B
19.A.
