Here something that might help
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Most scientists believe that for half of </span>Earth's<span> 4.6-billion-year history, the</span>atmosphere<span> contained almost no </span>oxygen<span>. Cyanobacteria or blue-green algae became the first microbes to produce </span>oxygen<span> by photosynthesis, perhaps as long ago as 3.5 billion years ago and certainly by 2.7 billion years ago.</span>
When a volcano erupts , a mixture of gases and particles is released into the air . The cooling influence of an individual volcano will dominate for the period immediately after the eruption but the warming impact will last much longer.
Dr. Haxton says the O-O bond is polar and the C-C bond is nonpolar. A good student would say ...
a.No, both bonds are highly polar.
b.Yes. O attracts electrons more strongly than C.
c.Right! O is electronegative, so O2 is polar.
d.Wrong again, Ralph. Both bonds are nonpolar. When two atoms of the same kind form a covalent bond, they share electrons equally because their electronegativity is the same.
e.No way. C is more electronegative than O.
Answer: d.Wrong again, Ralph. Both bonds are nonpolar. When two atoms of the same kind form a covalent bond, they share electrons equally because their electronegativity is the same.
Explanation:
Often when O and H are present in the substance at (opposite) ends (of the electronegativity scale), the polarity observed is very large, we can safely say the substance have a polar bond in it.
Answer:
All of the above. is correct
Explanation:
