The number of mole of HCl needed for the solution is 1.035×10¯³ mole
<h3>How to determine the pKa</h3>
We'll begin by calculating the pKa of the solution. This can be obtained as follow:
- Equilibrium constant (Ka) = 2.3×10¯⁵
- pKa =?
pKa = –Log Ka
pKa = –Log 2.3×10¯⁵
pKa = 4.64
<h3>How to determine the molarity of HCl </h3>
- pKa = 4.64
- pH = 6.5
- Molarity of salt [NaZ] = 0.5 M
- Molarity of HCl [HCl] =?
pH = pKa + Log[salt]/[acid]
6.5 = 4.64 + Log[0.5]/[HCl]
Collect like terms
6.5 – 4.64 = Log[0.5]/[HCl]
1.86 = Log[0.5]/[HCl]
Take the anti-log
0.5 / [HCl] = anti-log 1.86
0.5 / [HCl] = 72.44
Cross multiply
0.5 = [HCl] × 72.44
Divide both side by 72.44
[HCl] = 0.5 / 72.4
[HCl] = 0.0069 M
<h3>How to determine the mole of HCl </h3>
- Molarity of HCl = 0.0069 M
- Volume = 150 mL = 150 / 1000 = 0.15 L
Mole = Molarity x Volume
Mole of HCl = 0.0069 × 0.15
Mole of HCl = 1.035×10¯³ mole
<h3>Complete question</h3>
How many moles of HCl need to be added to 150.0 mL of 0.50 M NaZ to have a solution with a pH of 6.50? (Ka of HZ is 2.3 x 10 -5 .) Assume negligible volume of the HCl
Learn more about pH of buffer:
brainly.com/question/21881762
Answer: D, splitting water into hydrogen and oxygen is a chemical change.
Answer:
Explanation:
We can use the Ideal Gas Law and solve for T.
pV = nRT
Data
p = 2.91 atm
V = 78.13 L
n = 3.07 mol
R = 0.082 06 L·atm·K⁻¹mol⁻¹
Calculations
Answer:
When you wash your hands with soap, it dislodges the dirt, grease, oils, and disease-ridden fecal matter particles on your hands by creating these micelles. Surrounded by the soap, the oil molecules become suspended and distributed in the water rather than stubbornly clinging to your skin.
<h3><u>Answer;</u></h3>
Fe2+(aq) + 2OH(aq) ----> Fe(OH)2(s)
<h3><u>Explanation;</u></h3>
We first write down the balanced equation for this reaction:
FeCl₂(aq) + 2NaOH(aq) → 2 NaCl(aq) + Fe(OH)₂(s)
This is a precipitation reaction, where two soluble salts are mixed together in solution forms to make a precipitate.
Then,we can now write the ionic equation for this reaction, that is:
Fe²⁺(aq) + 2Cl⁻(aq) + 2 Na⁺(aq) + 2OH⁻ (aq) → 2 Na⁺(aq) + 2Cl⁻(aq) + Fe(OH)₂(s)
Now, we need to cancel the spectator ions, which are ions that are present on both sides in the equation.
So, the equation becomes;
Fe2+(aq) + 2OH(aq) ----> Fe(OH)2(s)
