Unsaturated hydrocarbons are those in which each carbon atom is attached to as many hydrogen atoms as it possibly can. There can be no double bonds or non-hydrogen functional groups, since these detract from the maximum possible number of hydrogens that each carbon can be attached to (in the case of double bonds, two carbons are bonded to each other when they could alternately be bonded to one more hydrogen each).
All of the alkanes (including the cycloalkanes) are saturated hydrocarbons. Substituted alkanes, alkenes, alkynes, and their cyclic counterparts are all unsaturated.
The density of the sample : 0.827 g/L
<h3>Further explanation</h3>
In general, the gas equation can be written

where
P = pressure, atm , N/m²
V = volume, liter
n = number of moles
R = gas constant = 0.082 l.atm / mol K (P= atm, v= liter),or 8,314 J/mol K (P=Pa or N/m2, v= m³)
T = temperature, Kelvin
n= 1 mol
MW Neon = 20,1797 g/mol
mass of Neon :

The density of the sample :

or We can use the ideal gas formula ta find density :

Answer: A heterogeneous mixture is a mixture in which its components retain their identity.
Why: Heterogeneous mixtures have several parts which can't be separated, like an italian dressing. Therefore, it's prefix is (hetero), which means something along the lines of "different". In a homogeneous mixture, it can be separated, and the prefix (homo) means "same".
Human use of land has negative impacts. Human activities contribute to the erosion and pollution of beaches. Deforestation of land can also lead to desertification and a loss of biodiversity.
Answer:
D.atom 2 is not the same , because the mass number is different from atoms 1 and 2