Answer:
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
Answer:One Astronomical Unit is the distance between the Earth and the Sun, this acts as a sort of a cosmic metre stick. Astronomers don't and cannot measure distances. Distances are merely inferred from what actually has been measured, such as an angle, a relative luminosity, a time period
Explanation:
Answer: 8.45 L
Explanation:
Given that,
Initial volume (V1) = 3.5L
Initial pressure (P1) = 2.5 atm
[Since final pressure is given in torr, convert 2.5 atm to torr
If 1 atm = 760 torr
2.5 atm = 2.5 x 760 = 1900 torr
Final volume (V2) = ?
Final pressure (P2) = 787 torr
Since pressure and volume are given while temperature remains the same, apply the formula for Boyle's law
P1V1 = P2V2
3.5L x 1900 torr = 787 torr x V2
6650L•torr = 787 torr•V2
Divide both sides by 787 torr
6650L•torr/787 torr = 787 torr•V2/787 torr
8.45 L = V2
Thus, the volume of the gas at 787 torr and at the same temperature is 8.45 Liters
Answer:
The bones of the skull and spinal column
Explanation:
The central nervous system is better protected than any other system or organ in the body. Its main line of defense is the bones of the skull and spinal column, which create a hard physical barrier to injury.
A.
Physical change
Step by step explanation;:)