<h3>
Answer:</h3>
52 mm
<h3>
Explanation:</h3>
We are given;
Required to convert it to cm
We are going to use the appropriate conversion factor;
- The units used to measure length include;
Kilometer(km)
10
Hectometer (Hm)
10
Decameter (dkm)
10
Meter(m)
10
Decimeter (dm)
10
Centimeter (cm)
10
Millimeter (mm)
Therefore; the appropriate conversion factor is 10mm/cm
Thus;
5.2 cm will be equivalent to;
= 5.2 cm × 10 mm/cm
= 52 mm
Therefore, the length of magnesium ribbon is 52 mm
The answer u are looking for is b
A buffer solution contains an equivalent amount of acid and base. The pH of the solution with an acid dissociation constant (pKa) value of 3.75 is 3.82.
<h3>What is pH?</h3>
The amount of hydrogen or the proton ion in the solution is expressed by the pH. It is given by the sum of pKa and the log of the concentration of acid and bases.
Given,
Concentration of salt [HCOO⁻] = 0.24 M
Concentration of acid [HCOOH] = 0.20 M
The acid dissociation constant (pKa) = 3.75
pH is calculated from the Hendersons equation as,
pH = pKa + log [salt] ÷ [acid]
pH = 3.75 + log [0.24] ÷ [0.20]
= 3.75 + log (1.2)
= 3.75 + 0.079
= 3.82
Therefore, 3.82 is the pH of the buffer.
Learn more about pH here:
brainly.com/question/27181245
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The answer should be D all of the above