Answer:
D
Explanation:
- The rate of the Diels-Alder is orders of magnitude faster if there is an electron-withdrawing group on the dienophile. For example, replacing a hydrogen on ethene with the electron-withdrawing group CN results in about a 10^5 increase in the reaction rate.
- Other common electron withdrawing functional groups that will accelerate the Diels Alder reaction of dienophiles include aldehydes, ketones, and esters.
- In short, any functional group conjugated with the pi bond which can act as a pi acceptor will accelerate a Diels-Alder reaction with a typical diene.
- See attachment for graphical explanation.
(1,500 meters) x (1 sec/330 meters) =
(1,500 / 330) (meters-sec/meters) =
4.55 seconds
Answer:
E = h*f = (6.63*10^-34) *( 3.8*10)
E = 2.5 *10^-32
Explanation:
e= Energy
h = Planck's constant
f = frequency
Answer:
1. Earth rotates on its axis; this causes us to experience day and night.
2. The speed of light is 186000 miles per second
3. The four seasons happen because of the tilt of the Earth's axis. At different times of the year, the sun's rays hit different parts of the globe more directly. The angle of the Earth's axis tilts the Northern Hemisphere towards the sun during the summer.
Explanation:
Use Coulomb law: F = k * q1*q2 / (r^2), where k = 9.00 * 10^9 N.m^2/C^2
F = 9.00 * 10^9 N.m^2/C^2 * 2.4*10^-8 C * 1.8*10^-6 C / [0.008m]^2 = 38.88 * 10^ -5 N
F = 39 * 10 -5N
