Which of the following explains how one of the postulates in John Dalton's atomic theory later became robust knowledge? (5 points) Select one: a. Some scientists found that some atoms of a particular element have different number of neutrons. b. Various scientists found that atoms combine in simple whole number ratios to form compounds. c. Some scientists found that atoms consist of subatomic particles with varying mass and charge. d. Various scientists found that sometimes a fraction of an atom can take part in a chemical reaction.

D!!!

Explanation:

THERE ARE NEVER FRACTIONS IN REACTIONS.

you can't have fractions when balancing equations because it wouldn't make sense to have 3/4 of a carbon atom when you cant just split atoms in ordinary chemical equations.

answer:

the answer is 6 valence electrons.

explanation:

valence is the # of electrons on the outer most shell of an atom.

oxygen has 6.

although, the valency of oxygen is 2, because it only needs to make 2 covalent bonds, or gain 2 electrons, to achieve the stable octet configuration of a noble gas.

that's it!

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