Bond energies can be used to estimate the energy of a reaction. Why is this only an estimate? A) It's difficult to measure such a smal amount of energy.

B) The bonds in all molecules are the same, but not all molecules have bonds that are easily measured.

C)The same bond in a different molecule has a different energy. For example, O-H in water versus ethanol has different energies.

D) It's difficult to isolate an individual bond.

C)The same bond in a different molecule has a different energy. For example, O-H in water versus ethanol has different energies.

Explanation:

This is true going by the the statement about the bond energies and the bonding being different among the various elements. In the example given which is between ethanol and water, the bonds which exist among the elements is stronger in water than in ethanol. That is why, ethanol is easily combustible than water.

The same bond in a different molecule has a different energy. For example, O-H in water versus ethanol has different energies.

Explanation:

in 1783 cavendish was working with his hydrogen gas and found that when he burned it and condensed the vapor it was water. this was very significant since it disproved the greek theory of elements completely since water was not a simple substance but the product of two gases. it was lavoisier who hearing of the experiment gave cavendish's gas the name hydrogen ("water-producer") and added that hydrogen burned by combining with oxygen and that water was a hydrogen-oxygen combination.

explanation: