O2.
Because it is only made up of one type of element it is an element. Howevern there is more than one oxygen atom because oxygen cannot exist as a single atom, therefore making it a molecule as well.
Answer:
(A) CHCH
Explanation:
Hello,
Alkynes are formed when triple bonds are formed between carbons, it means that due to the triple bonds, three bonds are already exhausted and carbon atoms need four bonds to attain the octet, for that reason, an extra bond is allowed. Now, such extra bond, when talking about hydrocarbons is filled with hydrogens, for that reason the alkyne should be (A) CHCH as it also accomplishes the following formula which is not accomplished by the rest of the options:

Since n=2, we have:

Which matches with CHCH.
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Answer:
what do you need help with .
Explanation:
?
Since there is no sample, let us assume 100 g of the solution:
(22.2% of 100 g) / (46.0254 g HCOOH/mol) = 0.48234 mol HCOOH
(100 g - 22.2 g) = 77.8 g = 0.0778 kg water
(0.48234 mol HCOOH) / (0.0778 kg) = 6.1997 mol/kg = 6.20 m HCOOH
(77.8 g H2O) / (18.01532 g H2O/mol) = 4.3185 mol H2O
(0.48234 mol HCOOH) / (0.48234 mol + 4.3185 mol) = 0.100 [the mole fraction of HCOOH]
Answer:
The answer is D.
Explanation:
Hold the styrofoam ball at arm's length from the eye.