Yes they are mixing. but they are not reacting.
methan
Generally speaking, methane gas can be "soluble" in liquid nitrogen if it was bubbled into it. Liquid nitrogen is cold enough to liquefy methane gas, and the liquid methane would then be miscible in the liquid nitrogen.
The fourth of the methane series. Methane, ethane, propane, butane, pentane, hexane, heptane, octane, ... Fourth is butane, like in a bic lighter.
Miscible in/with what? I am going to assume in water. Then, yes, they are miscible.
CBr4
Yes they are mixing. but they are not reacting.
Water and octane are practically non miscible.
methan
Yes it is. Because they are both not polar.
If you meant C8H18, it is an octane-isomer, than the answer is NO, not miscible with water. Petrol contains a lot (>50%) of octane molecules.
Octane and methane are both saturated hydrocarbons and follow the formula CnH2n+2. The only thing that's different is the number of carbons (and hence hydrogens) in the backbone. Octane has 8 carbons and has formula C8H18. Methane has 1 carbon and has formula C1H4.
Generally speaking, methane gas can be "soluble" in liquid nitrogen if it was bubbled into it. Liquid nitrogen is cold enough to liquefy methane gas, and the liquid methane would then be miscible in the liquid nitrogen.
The fourth of the methane series. Methane, ethane, propane, butane, pentane, hexane, heptane, octane, ... Fourth is butane, like in a bic lighter.
All these are saturated hydrocarbons of Alkane family.
Octane is an alkane hydrocarbon with the chemical formula C8H18.
propane