Answer: 
Explanation: Hydrocarbons are the compounds which contain only carbon and hydrogen as their constituent elements. These are considered to be as the non polar species as because of the less electronegativity difference between the two components.
Now as it is a non polar species thus it will dissolve only a non polar solute following the principle of 'Like dissolves Like'. Thus the most non polar species given in the options is pentane. Cyclohexane will definitely dissolve this pentane as both are non polar in nature.
, HI and NaBr are polar specie which cannot be dissolved in non polar species.
C. Oxidized and reduced are the same.
Answer:
it is less dense than oxygen gas.
Explanation:
Hydrogen is the simplest chemical element that exists. The symbol for the chemical element Hydrogen is "H" and it is a colourless, tasteless, odorless, and highly flammable gas.
Hydrogen is a chemical element found in group (1) of the periodic table and as such it has one (1) electrons in its outermost shell. Therefore, Hydrogen has an atomic number of one (1) and a single valence electrons because it has only one proton and one electron in its nucleus.
In Chemistry, the properties of a chemical element that can be observed and measured without changing its chemical nature is known as a physical property. It includes density, color, freezing point, opacity, smell, melting point, viscosity, etc.
Hence, the statement which describes a physical property of hydrogen is that it is less dense (density) than oxygen gas.
I'm not sure but I think it is A. image one has the most spread out particles like a gas, and b has closer together particles like a liquid or solid. since there are no choices that say A=gass and B=solid, so I am guessing it is answer A.
Answer:
A positive and negative ion.
Explanation:
Ionic bond:
It is the bond which is formed by the transfer of electron from one atom to the atom of another element.
Both bonded atoms have very large electronegativity difference.
The atom with large electronegativity value accept the electron from other with smaller value of electronegativity.
For example:
Sodium chloride is ionic compound. The electronegativity of chlorine is 3.16 and for sodium is 0.93. There is large difference is present. That's why electron from sodium is transfer to the chlorine. Sodium becomes positive and chlorine becomes negative ion. Sodium have one valance electron while chlorine have 7 valance electrons. In order to complete the octet chlorine require one electron while sodium need to lose its one electrons. That's why when both atom combine sodium lose its electron and becomes positive ion i.e cation while chlorine accept its electron and becomes negative ion called anion and bond between them is ionic bond.