Answer 1:
Isomers are compounds with same molecular formula but different structure formula. Isomers are classified into two types
a) Structural/configurational isomers
b) Stereo isomers
In structural/configurational isomers atom and functional groups are attached in different fashion. Structural isomers may have different functional groups. Structural isomers are further classified as chain isomers, position isomers and functional isomers. In case of stereo-isomers, compounds have same functional group, but different orientation in space. They also have difference activity towards polarized light.
Answer 2:
Hexane has a molecular formula of C6H14. It exhibits following structural isomers
a) hexane<span>,
b) 2-methylpentane
c)3-methylpentane
d) 2,2-dimethylbutane
e) 2,3-dimethylbutane
Thus, in all there are 5 isomers of hexane
Answer 3:
</span><span>Butane has two possible isomers but that decane has 75 possible isomers. This can be attributed to the fact that butane has 4 carbon atoms, while decane has 10 carbon atom. As the number of carbon atom increases, there are higher possible sites of linkage, in different fashion. Therefore, as number 69 of carbon atoms increases, number of different possible isomers increases.
Answer 4:
It has been observed that, though isomers have same molecular formula, but the have different boiling points. Infact, branched isomers have lower boiling point as compared to linear isomers. For example, hexane has boiling point = 69 oC, 2 methyl pentane has boiling point = 60 oC, 2,4, dimethyl butane has boiling point = 58 oC and 2,2 dimethyl butane has boiling point = 50 oC. Thus, it can be observed that branched isomers have lower boiling points as compared to linear isomers. This can be attributed to lower van der Waal's forces of interaction in branched isomers as compared to linear isomers.
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In this item, we are simply to find the ions that may bond and are able to form a formula unit. We are also instructed to give out their name. There are numerous possible combinations of ions to form a compound. Some answers are given in the list below.
1. Na⁺ , Cl⁻ , NaCl ---> sodium chloride (this is most commonly known as table salt)
2. C⁴⁺ , O²⁻ , CO₂ ---> carbon dioxide
3. Al³+ , Cl⁻ , AlCl₃ ----> aluminum chloride
4. Ca²⁺ , Cl⁻ , CaCl₂ ---> calcium chloride
5. Li⁺ , Br⁻ , LiBr ---> lithium bromide
6. Mg³⁺ , O²⁻ , Mg₂O₃ ----> magnesium oxide
7. K⁺ , I⁻ , KI ---> potassium iodide
8. H⁺ , Cl⁻ , HCl --> hydrogen chloride
9. H⁺ , Br⁻ , HBr ----> hydrogen bromide
10. Na⁺ , Br⁻ , NaBr ---> sodium bromide
Answer:
a. A reaction in which the entropy of the system increases can be spontaneous only if it is endothermic.
Explanation:
The change in free energy (ΔG) that is, the <u>energy available to do work</u>, of a system for a constant-temperature process is:

-
When ΔG < 0 the reaction is spontaneous in the forward direction.
- When ΔG > 0 the reaction is nonspontaneous. The reaction is
spontaneous in the opposite direction.
- When ΔG = 0 the system is at equilibrium.
If <u>both ΔH and ΔS are positive</u>, then ΔG will be negative only when the TΔS term is greater in magnitude than ΔH. This condition is met when T is large.