D is an alkene because the ending is cis-2-pentene if it was an alkane is would be pentane.
19.927 moles are in 1.20 times 
atoms of phosphorus.
<h3>What are moles?</h3>
A mole is defined as 6.02214076 ×
of some chemical unit, be it atoms, molecules, ions, or others.
1 mole of any substance contain Avogadro's number of molecules so we can calculate the number of moles by dividing the provided number of atoms over Avogadro's number to obtain the number of moles .
Moles= 
Moles= 1.20 X atoms ÷ 6.022 X
= 19.927
Hence, 19.927 moles are in 1.20 times atoms of phosphorus.
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Answer:
Option b. 22 g of He will have the greatest volume at STP
Explanation:
In order to determine the volume, we apply the Ideal Gases Law equation:
P . V = n . R . T
V = n . R . T / P
R, T and P are the same in all the situation we must define n (number of moles).
The one that has the greatest number of moles will have the greatest volume at STP
22 g of Ne . 1mol / 20.1 g = 1.09 moles of Ne
22g of He . 1mol / 4 g = 5.5 moles of He
22 g of O₂ . 1mol / 32g = 0.68 moles of O₂
22 g of Cl₂ . 1mol / 70.9 g = 0.31 moles of Cl₂
Answer:
3.59x10^21 molecules
Explanation:
1mole of a substance contains 6.02x10^23 molecules.
Therefore, 1mole of C8H18 will also contain 6.02x10^23 molecules
1mole of C8H18 = (12x8) +(18x1) = 96 + 18 = 114g.
1mole (i.e 114g) oh C8H18 contains 6.02x10^23 molecules.
Therefore, 0.68g of C8H18 will contain = (0.68 x 6.02x10^23)/114 = 3.59x10^21 molecules
