Bismuth(III) Sulfide is a brownish powder that is soluble in acids.
Answer:
3.74%
Explanation:
We express a solution's volume by volume percent concentration, % v/v,
Take the ratio of the isopropyl alcohol (IPA) volume to the total volume of the solution, which is 1800 mL of water+ 70 mL of IPA,
and multiply by 100 to get the percentage: 70/(1800+70) *100 = 0.0374*100 = 3.74%
Answer:
224 grams of O₂
Explanation:
This is the reaction:
2 C₂H₆ (g) + 7 O₂(g) → 4 CO₂ (g) + 6 H₂O (g)
2 moles of ethene react with 7 moles of oxygen.
Let's convert the ethene's mass into moles (mass / molar mass)
60 g / 30 g/m = 2 mol
So, if 2 moles of ethene must react with 7 moles of O₂ and we have 2 moles, obviously we would need 7 moles of oyxgen.
Let's convert the moles to mass ( mol . molar mass)
7 m . 32 g/m = 224 grams
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
It broke up in the Mesozoic era.
