Explanation:
(a) mass number = atomic number + number of neutrons
(the atomic number is the number of protons of an element)
mass number of A = 11 + 12 = 23
mass number of B = 17 + 18 = 35
(b) +1 and -1, respectively
(c) A+ + B- → AB (the first plus sign and the minus sign are superscripts)
I think the correct answer would be A. When a polonium atom with 84 protons, 124 neutrons, and 84 electrons undergoes alpha decay, a lead atom would be produced with 82 protons, 122 neutrons, and 84 electrons together with an alpha particle having two protons and two neutrons.
For this reaction to proceed, the following bond breaking should occur:
*one C-H bond
* one Cl-Cl bond
After, the following bond formations should occur:
*one C-Cl bond
*one H-Cl bond
Now, add the bond energies for the respective bond energies which can be found in the attached picture. For bond formations, energy is negative. For bond breaking, energy is positive.
ΔHrxn = (1)(413) + (1)(242) + 1(-328) + 1(-431) =
<em>-104 kJ</em>
Absolute dating is finding the exact date of an artifact such as a fossil using a technique such as radioactive dating, etc.
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