Answer: the answer is number 3 which is 6
<span>Avogadro's number
represents the number of units in one mole of any substance. This has the value
of 6.022 x 10^23 units / mole. This number can be used to convert the number of
atoms or molecules into number of moles.
163 g Ca (1 mol / 40.08 g) ( </span>6.022 x 10^23 atoms / 1 mol ) = 2.45 x10^24 atoms Ca
B) ionic bond
(although in reality, every bond is fundamentally the sharing of a pair of electron. but due to unmutal electonegativity, the molecule becomes polar)
Mass number = number of protons + number of neutrons
number of protons = atomic number =7
number of neutrons= mass number - number of protons=16-7=9
Answer is B.9.
