Allene (1,2-propadiene) has point group D2d, itself is achiral because it has two planes of symmetry. ... An allene with substituents on one terminal carbon atom are unlike and substituent on other terminal carbon atoms are same, allene will be achiral. It will have one symmetry plane.
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Because in difrent materials atoms are more compact or less compact.if they are less compact then it will be easear for them to move
Answer: scientific explanation
Explanation:
A really good scientific explanation should do two main things: It should explain all the observations and data we have. It should allow us to make testable predictions that we can check using future experiments.
Binary Stars I think
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