pH=4.625
The classification of this sample of saliva : acid
<h3>Further explanation</h3>The water equilibrium constant (Kw) is the product of concentration
the ions:
Kw = [H₃O⁺] [OH⁻]
Kw value at 25° C = 10⁻¹⁴
It is known [OH-] = 4.22 x 10⁻¹⁰ M
then the concentration of H₃O⁺:
pH=-log[H₃O⁺]
Saliva⇒acid(pH<7)
<u>Answer:</u> The theoretical yield of iron(III) sulfate is 26.6 grams
<u>Explanation:</u>
To calculate the number of moles, we use the equation:
.....(1)
Given mass of iron(III) phosphate = 20.00 g
Molar mass of iron(III) phosphate = 150.82 g/mol
Putting values in equation 1, we get:
The given chemical equation follows:
As, sodium sulfate is present in excess. So, it is considered as an excess reagent.
Thus, iron(III) phosphate is considered as a limiting reagent because it limits the formation of product.
By Stoichiometry of the reaction:
2 moles of iron(III) phosphate produces 1 mole of iron(III) sulfate
So, 0.133 moles of iron(III) phosphate will produce = of iron(III) sulfate
Now, calculating the mass of iron(III) sulfate from equation 1, we get:
Molar mass of iron(III) sulfate = 399.9 g/mol
Moles of iron(III) sulfate = 0.0665 moles
Putting values in equation 1, we get:
Hence, the theoretical yield of iron(III) sulfate is 26.6 grams
Answer:
Explanation:
Hello there!
In this case, we can divide the problem in three stages: (1) determine the empirical formula with the combustion analysis, (2) compute the molar mass of acid via the moles of the acid in the neutralization and (3) determine the molecular formula.
(1) In this case, since 8.58 g of carbon dioxide are released, we can first compute the moles of carbon in the compound:
And the moles of hydrogen due to the produced 1.50 grams of water:
Next, to compute the mass and moles of oxygen, we need to use the initial 3.4 g of the acid:
Thus, the subscripts in the empirical formula are:
As they cannot be fractions.
(2) In this case, since the acid is monoprotic, we can compute the moles by multiplying the concentration and volume of KOH:
Which are equal to the moles of the acid:
And the molar mass:
(3) Finally, since the molar mass of the empirical formula is:
7*12.01 + 6*1.01 + 2*16.00 = 122.13 g/mol
Thus, since the ratio of molar masses is 122.86/122.13 = 1, we infer that the empirical formula equals the molecular one:
Best regards!