The answer is A :) your welcome hope this helps
The first bond between two atoms is always a sigma bond and the other bonds are always pi bonds and a hybridized orbital cannot be involved in a pi bond. Thus we need to leave one electron (in case of Carbon double bond) to let the Carbon have the second bond as a pi bond.
Answer:
Part A: 36 MBq; Part B: 18 MBq
Explanation:
The half-life is the time it takes for half the substance to disappear.
The activity decreases by half every half-life
A =Ao(½)^n, where n is the number of half-lives.
Part A
3.0 da = 1 half-life
A = Ao(½) = ½ × 72 MBq = 36 MBq
Part B
6.0 da = 2 half-lives
A = Ao(½)^2 = ¼ × 72 MBq = 18 MBq
Answer:
B.Bronze is harder than copper, so it retains a cutting edge sharper than that of copper.
Explanation:
The importance of bronze in the history of the human kind can not be only measured in the durability but the help that it provided to our ancestors, the things they were allowed to do once they dicovered how to mold it, and the tools that they produced and made many every day tasks easier for them and the ability of bronze to mantain the cutting edge longer than copper was one of the main reasons why it took its places in the fabrication of many tools.
