I believe the answer is A the 1st one
The pH of the solution in which one normal adult dose aspirin is dissolved is : 2.7
Given data :
mass of aspirin = 640 mg = 0.640 g
volume of water = 10 ounces = 0.295735 L
molar mass of aspirin = 180.16 g/mol
moles of aspirin = mass / molar mass = 0.00355 mol
<h3>Determine the pH of the solution </h3>
First step : <u>calculate the concentration of aspirin</u>
= moles of Aspirin / volume of water
= 0.00355 / 0.295735
= 0.012 M
Given that pKa of Aspirin = 3.5
pKa = -logKa
therefore ; Ka = 
= 
From the Ice table
= ![\frac{x + H^+}{[aspirin]}](https://tex.z-dn.net/?f=%5Cfrac%7Bx%20%2B%20H%5E%2B%7D%7B%5Baspirin%5D%7D)
= 
given that the value of Ka is small we will ignore -x
x² = 
x = 
Therefore
[ H⁺ ] =
given that
pH = - Log [ H⁺ ]
= - ( -3 + log 1.948 )
= 2.71 ≈ 2.7
Hence we can conclude that The pH of the solution in which one normal adult dose aspirin is dissolved is : 2.7
Learn more about Aspirin : brainly.com/question/2070753
Answer: 2 (2 neutrons are produced).
Explanation:
1) In the left side of the transmutation equationa appears:
²³⁵U + ¹n →
I am omitting the atomic number (subscript to the leff) because the question does not show them as it is focused on number of neutrons.
2) The right side of the transmutation equation has:
→ ¹⁴⁴Ce + ⁹⁰Sr + ?
3) The total mass number of the left side is 235 + 1 = 236
4) The total mass number of Ce and Sr on the right side is 144 + 90 = 234
5) Then, you are lacking 236 - 234 = 2 unit masses on the right side which are the 2 neutrons that are produced along with the Ce and Sr.
The complete final equation is:
²³⁵U + ¹n → ¹⁴⁴Ce + ⁹⁰Sr + 2 ¹n
Where you have the two neutrons produced.
We are told that KOH is being used to completely neutral H₂SO₄ according to the following reaction:
KOH + H₂SO₄ → H₂O + KHSO₄
If KOH can completely neutralize H₂SO₄, then there must be an equal amount of moles of each as they are in a 1:1 ratio:
0.025 L x 0.150 mol/L = .00375 mol KOH
0.00375 mol KOH x 1 mole H₂SO₄/1 mole KOH = 0.00375 mol H₂SO₄
We are told we have 15 mL of H₂SO₄ initially, so now we can find the original concentration:
0.00375 mol / 0.015 L = 0.25 mol/L
The concentration of H₂SO₄ being neutralized is 0.25 M.
Answer: % Errror = 11.05%
Explanation:
Percentage error is the difference between the measured value and the theoretical value as expressed in percent.
That is;
% Error =
( Theoretical value -measured value) /(Theoretical value) × 100
Theoretical value =55.2kJ
Measured value = 49.1kJ
% Error = (55.2-49.1)/(55.2) ×100
%Error = 6.1/55.2 ×100
% Error = 0.1105 ×100
% Error = 11.05
Therefore the percentage error is 11.05%
