<span>Answer:
The HCl and KOH will react until one or the other is gone. As you have a larger volume of an equal concentration of HCl, the KOH will go first.
moles HCl = 0.04000 L * 0.100 M = 0.00400 moles
moles KOH = 0.02500 L * 0.100 M = 0.00250 moles
moles HCl left = 0.00400 - 0.00250 = 0.00150 moles
Your total volume is now 65.00 mL, so the [HCl] = 0.00150 moles / 0.06500 L = 0.0231 M = [H+]
pH = -log [H+] = -log (0.0231) = 1.64</span>
Answer:
The minimum number of boxes of pencils to be ordered is 630 boxes.
Explanation:
Since a pupil uses averagely 9.3 pencils
and a box contains 12 pencils,
the school enrollment is also 812
school's enrollment x average use of pencil per student
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number of pencils in a box
812 x 9.3 = 7551.6
7551.6 /12 = 629.3
Having a total number of 630 boxes of pencils to be ordered.
