Given the following equations, calculate the δh of the reaction of ethylene gas (c2h4) with fluorine gas to make carbon tetrafluoride (cf4) gas and hydrogen fluoride gas. show your work. h2 (g) + f2 (g) → 2hf (g) δh = –537 kj c (s) + 2f2 (g) → cf4 (g) δh = –680 kj 2c (s) + 2h2 (g) → c2h4 (g) δh = +52.3 kj

Answer is: the ΔH of the reaction is -2486.3 kJ.

Chemical reaction 1: H₂(g) + F₂(g) → 2HF(g)ΔH₁ = –537 kJ.

Chemical reaction 2: C(s) + 2F₂(g) → CF₄(g) ΔH₂ = –680 kJ.

Chemical reaction 3: 2C(s) + 2H₂(g) → C₂H₄(g) ΔH₃ = +52.3 kJ.

Chemical reaction 4: C₂H₄(g) + 6F₂(g) → 2CF₄(g) + 4HF(g) ΔH₄ = ?

Using Hess's law:

ΔH₄ = 2ΔH₁ + 2ΔH₂ - ΔH₃.

ΔH₄ = 2 · (-537 kJ) + 2 · (-680 kJ) - 52.3 kJ.

ΔH₄ = -2486.3 kJ.

both adhesion and cohesion are attractions.

they are different in that adhesion is the force of attraction between the molecules of two different substances, whereas cohesion is the force of attraction between molecules of the same substance.

possible examples include capillary action, in which the adhesion between water and glass causes the water to rise in a narrow tube against the force of gravity.

because of hydrogen bonding, water is extremely cohesive.

this causes molecules on the surface of water to be drawn inward, which is why drops of water form beads on smooth surfaces.

hope this .

substituting a hydrogen atom with a halogen in a hydrocarbon:

- the single bond remains single. a is wrong.

- the bond with hydrogen is as strong as with a halogen. c is wrong

- a hydrocarbon is saturated if there is no double bond. we do not know that so d is wrong.

- carbon will always have four valence electrons. e is wrong.

by elimination, the correct answer is b. the boiling point of the new compound increases.