Percent composition by mass of oxygen =
((16.0*6)/(40.1+2*(14.0+16.0*3)))*100%
= 58.5%
therefore, the answer is D
Good electrical conductivity and electronegativities less than 1.7 are the properties and characteristic of Group 2 elements at STP.
<h3>What are the properties of group 2 elements?</h3>
Group 2 elements are metals so they are good conductors of heat and electricity. It has electronegativity values less than 1.7 and very reactive. They form 2+ charge in cationic form and also formed ionic bonds with other negatively charged elements.
So we can conclude that good electrical conductivity and electronegativities less than 1.7 are the properties and characteristic of Group 2 elements at STP.
Learn more about electronegativity here: brainly.com/question/2415812
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11 with pemdas, you have to multiply all by 3
Answer:
In first shell 2 electrons are present and 7 electrons are present in last shell
Explanation:
