Answer:
The final volume in mL is 7.14 mL or 7.1 mL.
Explanation:
1.Use Boyle's Law(
). Re-arrange to solve for 
<em> for the final volume.</em>
<em />
<em>2. Plug in values. </em>
D) Chlorine, Cl. Hope that helped
The most correct answer is A. Scientists would conduct a study to discover the amount of biodiversity in the area. From that point onward, if it is found that there is a low biodiversity that may be negatively impacted by construction, scientists would perform further tests such as water quality analyses and comparing their data to other, similar sites. Environmental law, in this case, would not prevent scientists from conducting a study, but would rather prevent developers from continuing until a complete survey of the land has been done.
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
When answering the above question or problem, <span>first thing to realize is that the dissolution of the Na3PO4 can be written in a format that may be easier to see what is happening here. </span>
<span>Na3PO4 ----> 3 Na(+) + PO4(-3) </span>
<span>Now, you are starting out with a 0.35 M solution of Na3PO4, but when you dissolve the Na3PO4 into solution there are 3 Na(+) ions made for every Na3PO4 molecule that dissolves. Therefore to calculate the concentration of Na(+) ions in the final solution, take 3 times the inital concentration. 0.35 * 3 = 1.05 M in Na(+)</span>
