Answer: Multiple covalent bonds may occur in atoms that contain carbon,nitrogen, or <u><em>oxygen</em></u>.
Alleles are inside a gene and genes are made up by alleles. Also, a gene is DNA, so the allele is like piece of DNA inside a gene<span>.
Hope this helps:)
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<span>Bleach and ammonia can be used to make cl2. Bleach is commercially available and so people should be very careful during these experiments or even when mixing things in the household.</span>
Physical change because it still has the same chemical formula
