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Molodets [167]
3 years ago
9

Humans first appeared in the _____ period.

Chemistry
2 answers:
Ira Lisetskai [31]3 years ago
6 0

Answer:

They first appeared in the fossil record around 66 million years ago, soon after the Cretaceous–Paleogene extinction event that eliminated about three-quarters of plant and animal species on Earth, including most dinosaurs.

Explanation:

vlabodo [156]3 years ago
4 0

Answer:

A or b I learned this in history

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Should we only write condensed formula in chemical equations (for lessons like carbon and compounds). What did your teachers say
Firlakuza [10]

Answer:

Here's what I get.

Explanation:

  • If your teachers don't ask for a specific type of formula, a condensed structural formula should be OK.
  • If they ask specifically for a structural formula or a bond-line formula, that is what you must give.

Bottom line: ask your teachers in advance what they expect.

7 0
3 years ago
A compound with the empirical formula CH 2 O has a formula mass of 180 g/mol. What is its molecular formula
olga nikolaevna [1]

Empirical formula mass

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  • 30g/mol

Molecular fornula mass:-180g/mol

  • n=Molecular formula mass/Empirical formula mass
  • m=180/30
  • n=6

Molecular formula:-

  • n×Empirical formula
  • 6(CH_2O
  • C_6H_12 O_6
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Delta waves are associated with a deep sleep~
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Difference between protons neutrons and electrons?
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