In order to synthesize a complex organic molecule, the
chemist should at least illustrate or imagine the bonds that are in need to be
cut down or to separate in order to obtain the compound that can be easily
changed.
Answer:
The wavelength the student should use is 700 nm.
Explanation:
Attached below you can find the diagram I found for this question elsewhere.
Because the idea is to minimize the interference of the Co⁺²(aq) species, we should <u>choose a wavelength in which its absorbance is minimum</u>.
At 400 nm Co⁺²(aq) shows no absorbance, however neither does Cu⁺²(aq). While at 700 nm Co⁺²(aq) shows no absorbance and Cu⁺²(aq) does.
Answer: C. Electrochemical cells involve oxidation-reduction reactions.
Explanation: Oxidation occurs at the anode, and reduction occurs at the cathode.
Answer:
A. 29.9
Explanation:
- An element can have differing numbers of neutrons in its nucleus, but it always has the same number of protons. The versions of an element with different neutrons have different masses and are called isotopes.
- The average atomic mass for an element is calculated by summing the masses of the element’s isotopes, each multiplied by its natural abundance on Earth.
<em>Average atomic mass of P = ∑(Isotope mass)(its abundance)</em>
∴ Average atomic mass of P = (P-29 mass)(its abundance) + (P-30 mass)(its abundance) + (P-31 mass)(its abundance) + (P-33 mass)(its abundance)
<em>Abundance of isotope = % of the isotope / 100.</em>
<em>∴ Average atomic mass of P =</em> (29)(0.327) + (30)(0.4803) + (31)(0.184) + (33)(0.0087) = <em>29.88 a.m.u ≅ 29.9 a.m.u.</em>
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<em>So, the right choice is: A. 29.9</em>
