To convert minutes to hours we divide the minutes by 60. So if we divide 3 by 60 we get 0.05 hours.
<h3>How to convert minutes into hour?</h3>
We know that in hour, there are 60 minutes so if we go from minutes to hours then we have to divide the number by 60 and when we go from hours to minutes we multiply with the same 60 number.
So we can conclude that to convert minutes to hours we divide the minutes by 60. So if we divide 3 by 60 we get 0.05 hours.
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Well assuming we have all of these, earth
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
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B
step-by-step explanation
Answer:
4.15×10⁻²¹ moles of Sn
Explanation:
This question can be solved by a simple rule of three.
We know that 1 mol contains 6.02×10²³ particles.
In this case, our particles are the atoms, so:
6.02×10²³ atoms / 1 mol . 2500 atoms = 4.15×10⁻²¹ moles.
The knowledge of mol can be applied for everything:
A mol of molecules
A mol of atoms
A mol of a compound