Industrial ethanol (CH3CH2OH) is produced by a catalytic reaction of ethylene (CH2═CH2) with water at high pressures and temperatures. Calculate ΔH o rxn for this gas-phase hydration of ethylene to ethanol, using bond energies and then using enthalpies of formation.

using bond energies = - 37 kJ

using enthalpies of formation = - 45.7 kJ

Explanation:

From the reaction;

CH2═CH2(g) + H2O(g) -------> CH3CH2OH(g)

From the above reaction; there are 4 (C-H) bonds , 1 ( C=C) and 2 (H-O) of ethene which forms 5(C-H) bonds, 1 (C-C) and 1 (C-O) and 1(H-O) bonds.

Using Bond Energies; the heat of the reaction can be written as:

∑ energy of old bond breaking + ∑ energies of the new bond formation.

∑ + ∑

∑+ ∑

 -37 kJ

To calculate the heats of reaction by using enthalpies of formation; we have:

∑ -  ∑

∑ - ∑

 (-235.1 kJ) - [(+52.47 kJ) + (-241.826 kJ)]

 -45.7 kJ

a: 45.9 meters

b: 4.29 seconds

step-by-step explanation:

a: h(t)=1/2(-9.8)(3)^2+0(3)+90

h(t)=-4.9(3)^2+90

h(t)=-44.1+90

h(t)=45.9 meters

b: 0=1/2(-9.8)(t^2)+0t+90

0=-4.9t^2+90

-90=-4.9t^2

18.37=t^2

t=4.29 seconds

in the second question, the numbers aren't exact, but they're a close approximation.

the number of protons in the nucleus of a given element. has slight luster and conducts electricity at high temperatures like metal.but like a nonmetal,boron is brittle and does not conduct electricity well at low temperatures. in graphite, carbon is a soft,brittle solid.it is reflective,ductile,or malleable.