Answer:
Multiply the number of moles in the product by the molecular weight of the product to determine the theoretical yield.
Explanation:
For example:
If you created 0.5 moles of Aluminium Oxide the molecular weight of Aluminium Oxide is 101.96g/mole, so you would get 50.98g as the theoretical yield.
So multiply,..
101.96x0.5= 50.98
This is the correct way to calculate the theoretical yield
......
Answer:
15.4 g of Zn₃(PO₄)₂ are produced
Explanation:
Given data:
Mass of zinc phosphate formed = ?
Volume of zinc nitrate = 48.1 mL (0.05 L)
Molarity of zinc nitrate = 2.18 M
Solution:
Chemical equation:
3Zn(NO₃)₂ + 2K₃PO₄ → Zn₃(PO₄)₂ + 6KNO₃
Moles of zinc nitrate:
Molarity = number of moles / volume in litter
Number of moles = 2.18 M × 0.05 L
Number of moles = 0.109 mol
Now we will compare the moles of zinc phosphate with zinc nitrate from balanced chemical equation:
Zn(NO₃)₂ : Zn₃(PO₄)₂
3 : 1
0.109 : 1/3×0.109 = 0.04 mol
0.04 moles of Zn₃(PO₄)₂ are produced.
Mass of Zn₃(PO₄)₂:
Mass = number of moles × molar mass
Mass = 0.04 mol × 386.1 g/mol
Mass = 15.4 g
Answer:
3,85 g of Fe
Explanation:
1- The first thing to do is calculate the molar mass of the Fe2O3 compound. With the help of a periodic table, the weights of the atoms are searched, and the sum is made:
Molar mass of Fe2O3 = (2 x mass of Fe) + (3 x mass of O) = 2 x 55.88 g + 3 x 15.99 g = 159.65 g / mol
Then, one mole of Fe2O3 has a mass of 159.65 grams.
2- Then, the relationship between the Fe2O3 that will react and the iron to be produced. With the previous calculation, we can say that with one mole of Fe2O3, two moles of Fe can be produced. Passing this relationship to the molar masses, it would be as follows:
1 mole of Fe2O3_____ 2 moles of Fe
159.65 g of Fe2O3_____ 111.76 g of Fe
3- Finally, the calculation of the mass that can be produced of Fe is made, starting from 5.50 g of Fe2O3
159.65 g of Fe2O3 _____ 111.76 g of Fe
5.50 g of Fe2O3 ______ X = 3.85 g of Fe
<em>Calculation: 5.50 g x 111.76 g / 159.65 g = 3.85 g
</em>
The answer is that 3.85 g of Fe can be produced when 5.50 g of Fe2O3 react
Answer:
e) pH is independent of concentration.
Explanation:
a) It is a mixture of a weak acid and its conjugate base. <em>TRUE. </em>A buffer is defined as a mixture of a weak acid and its conjugate base or a weak base and its conjugate acid.
b) Resists pH changes because it reacts with added acid or base. <em>TRUE. </em>Thermodynamically, the reaction of added acid or base is faster with the buffer mixture than with H⁺ or OH⁻ ions of the solutions.
c) The maximum buffer capacity is at pH = pKa. <em>TRUE. </em>The buffer capacity is pka±1. For this, buffer capacity is maximum in pka.
d) pH is dependent on the solution ionic strength and temperature. <em>TRUE.</em> Ionic strength and temperature are factors that influence concentrations of ions in solutions as the H⁺ ion that is the responsible
e) pH is independent of concentration. <em>FALSE. </em>pH in a buffer depends completely of concentrations of the acid and its conjugate base or vice versa.
I hope it helps!
