Answer:
HC₂H₃O₂/KC₂H₃O₂
Explanation:
Considering the Henderson- Hasselbalch equation for the calculation of the pH of the basic buffer solution as:
![ pH=pK_b+log\frac{[salt]}{[acid]} ](https://tex.z-dn.net/?f=%0ApH%3DpK_b%2Blog%5Cfrac%7B%5Bsalt%5D%7D%7B%5Bacid%5D%7D%0A)
For a best pair, the pKa value must be equal to pH.
NH₃/NH₄Cl forms a basic buffer and cannot account for pH = 5
out of the acidic buffer given,
So, HF , Ka = 3.5 × 10⁻⁴ , So pKa = 3.46
HC₂H₃O₂ , Ka = 1.8 × 10⁻⁵ , So pKa = 4.77
<u>The best pair to show pH = 5 is HC₂H₃O₂/KC₂H₃O₂</u>
Answer:
10.5grams
Explanation:
Molarity = number of moles (n)/ volume (V)
According to this question;
Volume = 750 mL = 750/1000 = 0.75L
Molarity = 0.35M
number of moles (n) = molarity × volume
n = 0.35 × 0.75
n = 0.2625mol
Using mole = mass/molar mass
Molar Mass of NaOH = 23 + 16 + 1
= 40g/mol
mole = mass/molar mass
0.2625 = mass/40
mass = 10.5grams
10.5 grams are needed to prepare 0.75L of a 0.35 M solution of NaOH.
Answer:
Fiber optics is the technology used to transmit information as pulses of light through strands of fiber made of glass or plastic over long distances.
Explanation:
I did a test on it before
<span>Each mole contains Avagodro's number of atoms i.e. 6.023x10^23, so
3 moles x 6.023x10^23 atoms/mole = 18.069x10^23 atoms = 1.8x19^24 atoms </span>
