Hey there!:
Molar mass of Mg(OH)2 = 58.33 g/mol
number of moles Mg(OH)2 :
moles of Mg(OH)2 = 30.6 / 58.33 => 0.5246 moles
Molar mass of H3PO4 = 97.99 g/mol
number of moles H3PO4:
moles of Mg(OH)2 = 63.6 / 97.99 => 0.649 moles
Balanced chemical equation is:
3 Mg(OH)2 + 2 H3PO4 ---> Mg3(PO4)2 + 6 H2O
3 mol of Mg(OH)2 reacts with 2 mol of H3PO4 ,for 0.5246 moles of Mg(OH)2, 0.3498 moles of H3PO4 is required , but we have 0.649 moles of H3PO4, so, Mg(OH)2 is limiting reagent !
Now , we will use Mg(OH)2 in further calculation .
Molar mass of Mg3(PO4)2 = 262.87 g/mol
According to balanced equation :
mol of Mg3(PO4)2 formed = (1/3)* moles of Mg(OH)2
= (1/3)*0.5246
= 0.1749 moles of Mg3(PO4)2
use :
mass of Mg3(PO4)2 = number of mol * molar mass
= 0.1749 * 262.87
= 46 g of Mg3(PO4)2
Therefore:
% yield = actual mass * 100 / theoretical mass
% = 34.7 * 100 / 46
% = 3470 / 46
= 75.5%
Hope that helps!
Answer: D.) 25.9%
Explanation:
Dinitrogen pentoxide chemical formular : N2O5
Calculating the molar mass of N2O5
Atomic mass of nitrogen(N) = 14
Atomic mass of oxygen(O) = 16
Therefore molar mass :
N2O5 = (2 × 14) + (5 × 16) = 28 + 80 = 108g/mol
Percentage amount of elements in N205:
NITROGEN (N) :
(Mass of nitrogen / molar mass of N2O5) × 100%
MASS OF NITROGEN = (N2) = 2 × 14 = 28
PERCENT OF NITROGEN : (28/108) × 100%
0.259259 × 100%
= 25.925%
= 25.9%
Answer:
5 1 2 4and 3 this is correct way
A is your answer.
On the periodic table the atomic number is the number of protons inside the nucleus.
Answer:
1.3×10⁻³ M
Explanation:
Hello,
In this case, given the dissociation reaction of acetic acid:
We can write the law of mass action for it:
![Ka=\frac{[H_3O^+][CH_3CO_2^-]}{[CH_3CO_2H]}](https://tex.z-dn.net/?f=Ka%3D%5Cfrac%7B%5BH_3O%5E%2B%5D%5BCH_3CO_2%5E-%5D%7D%7B%5BCH_3CO_2H%5D%7D)
Of course, excluding the water as heterogeneous substances are not included. Then, in terms of the change 
due to the dissociation extent, we are able to rewrite it as shown below:
Thus, via the quadratic equation or solve, we obtain the following solutions:
Obviously, the solution is 0.00133M which match with the hydronium concentration, thus, answer is: 1.3×10⁻³ M in scientific notation.
Regards.
