I think the answer is a or d
Answer:
Mg²⁺
Explanation:
The electron configuration of Mg is [Ne]3s².
It is easier for Mg to get a complete octet by losing two electrons and exposing the neon core than it is to add eight electrons and get an Ar octet.
The most stable monatomic Mg ion is Mg²⁺.
The number of years required for 1/4 cobalt-60 to remain after decay is calculated as follows
after one half life 1/2 of the original mass isotope remains
after another half life 1/4 mass of original mass remains
therefore if one half life is 5.3 years then the years required
= 2 x 5.3years = 10.6 years
Answer:
See Explanation
Explanation:
Given:
moles M = 0.600 mole
moles F = excess (for rxn stoichiometry)
Formula Weight (F.Wt.) of F = 19 grams/mole (from Periodic Table)
Yield in grams = 46.8 grams (assuming theoritical yield)
Rxn: M + F₂ => MF₂
0.600mol Excess 0.600mol (1:1 rxn ratio for M:MF₂)
a. moles of F in MF₂ = 2(0.600) moles F = 1.2 moles F
b. mole weight MF₂ = 46.8g/0.600mol = 78g/mole
F.Wt. MF₂ = F.Wt. M + 2(F.Wt. F)
=> mass M = F.Wt. M = [F.Wt. MF₂ - 2(F.Wt. F)] = 78g/mol. - 2(19g/mol.)
= (78 - 38) grams/mole = 40 grams/mole
c. Calcium (Ca) has F.Wt. = 40 grams/mole (compared to Calcium on Periodic Table.