Answer:
HC₂H₃O₂/KC₂H₃O₂
Explanation:
Considering the Henderson- Hasselbalch equation for the calculation of the pH of the basic buffer solution as:
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>
The specific activity (in Ci/g) if 1.65 mg of an isotope emits 1.56X10⁶α a particles per second.
<h3>What is isotope?</h3>
Isotopes are two or more types of atoms with the same atomic number (number of protons in their nuclei) and periodic table position (and so belong to the same chemical element), but distinct nucleon numbers due to differing numbers of neutrons in their nuclei. While all isotopes of a given element have nearly identical chemical properties, their atomic weights and physical properties differ.
The term isotope is derived from the Greek roots isos and topos, which means that different isotopes of the same element occupy the same position on the periodic table. Margaret Todd, a Scottish doctor and writer, coined the phrase in 1913 as a recommendation to British chemist Frederick Soddy.
To learn more about isotopes visit:
brainly.com/question/11680817
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<span>Cellular respiration is the chemical reaction in which glucose and oxygen are turned into water, carbon dioxide, and energy. Now you know the answer. :P</span>