Match these items.

1. umbra of moon touches the Earth
total lunar eclipse
2. penumbra of moon touches the Earth
partial lunar eclipse
3. umbra of Earth touches the moon
total solar eclipse
4. penumbra of Earth touches the moon
partial solar eclipse

thats how its supposed to be

because natural gas is colorless, odorless, and tasteless, distributors add mercaptan (a chemical that smells like sulfur) to give natural gas a distinct unpleasant odor (it smells like rotten eggs). they locate the types of rock that are likely to contain natural gas deposits.

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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~ trueboss72