Table of Contents
- 1 Why do alcohols with more carbon atoms release more energy when burned?
- 2 What happened to the properties of alcohol as the number of carbon increase?
- 3 How does number of carbon affect enthalpy of combustion?
- 4 How does increasing the number of carbon atoms in an alcohol affect the enthalpy change of combustion of the alcohol?
- 5 Why does alcohol solubility decrease as chain length increases?
- 6 Why does the combustion of alcohols release less energy than alkanes?
- 7 Why does enthalpy increase with carbon chain length?
- 8 Do longer carbon chains release more energy?
Why do alcohols with more carbon atoms release more energy when burned?
Your carbon atoms in the alcohol refers to the number of carbon bonds broken and each bond releases a finite amout of potential energy into heat. More bonds more energy.
What happened to the properties of alcohol as the number of carbon increase?
The boiling point of an alcohol is always much higher than that of the alkane with the same number of carbon atoms. The boiling points of the alcohols increase as the number of carbon atoms increases.
How does number of carbon affect enthalpy of combustion?
The higher the number of carbon is in the hydrocarbon chain, the greater the enthalpy change of combustion of the primary alcohol.
What is the relationship between the number of carbon atoms in the alcohol and the amount of oxygen required for combustion?
when 1 mole of a fuel is burned completely in oxygen….Expiremnt on Combustion and the Number of Carbon Atoms in an Alcohol Chain.
| Formula to process data | Sample calculation for ethanol |
|---|---|
| Heat of combustion = mcΔt | Heat of combustion = 100 x 4.168 x 62.58 = 26196 j =26.20 kj |
Why do larger alcohols release more energy?
Since a longer carbon chain lengths contain more C-H and C-C bonds (more bond energies) which produce more C=O. and O-H bonds ( and ); more bonds would be needed to break and larger level of energy released.
How does increasing the number of carbon atoms in an alcohol affect the enthalpy change of combustion of the alcohol?
The more carbons the alcohol has the more C=O bonds will be formed-actually for each C two of such bonds are formed- and this leads me to say that the enthalpy change should be directly increasing.
Why does alcohol solubility decrease as chain length increases?
Alcohols are soluble in water. The reason why the solubility decreases as the length of hydrocarbon chain increases is because it is requires more energy to overcome the hydrogen bonds between the alcohol molecules as the molecules are more tightly packed together as the size and mass increases.
Why does the combustion of alcohols release less energy than alkanes?
Hydrogen bonding In the case of alcohols, hydrogen bonds occur between the partially-positive hydrogen atoms and lone pairs on oxygen atoms of other molecules. Hydrogen bonds are much stronger than these; therefore, more energy is required to separate alcohol molecules than to separate alkane molecules.
How does increasing the carbon chain length affect energy released?
By investigating the energy produced during the combustion of different fuels, a linear increasing relationship (Figure 3) was discovered that the longer the carbon chain lengths (larger molar mass) in each fuel molecule, the higher energy released during combustion.
Does more carbon atoms mean more energy?
The more hydrogen per carbon, the lower the oxidation state and the more energy that will be released during the oxidation reaction. Thus the greater the H/C ratio, the more energy release on combustion.
Why does enthalpy increase with carbon chain length?
The bonds between C and O are double and therefore stronger than those between carbons which are simple. The more carbons the alcohol has the more C=O bonds will be formed-actually for each C two of such bonds are formed- and this leads me to say that the enthalpy change should be directly increasing.
Do longer carbon chains release more energy?
Actually, the shorter the chain, the more energy per gram. Hydrogen has more energy per gram than alkanes (but is harder to store). It is not true that longer chain hydrocarbons or carbohydrates contain more energy.