Which best explains why the pencil seems bent?

Select the statements that are TRUE. Electrophilic aromatic substitution reactions have energies of activation that are very low

NikAS [45]

Answer:

Addition reactions with benzenes lead to the loss of aromaticity.

Benzene and its derivatives undergo a type of substitution reaction in which a hydrogen atom is replaced by a substituent, but the stable aromatic benzene ring is regenerated at the end of the mechanism.

Benzene and its derivatives tend to undergo electrophilic aromatic substitution reactions.

Explanation:

5 0

3 years ago

620 J of heat is added to the cylinder of an engine, which causes the gas inside to expand. As a result, the piston of the engin

Maru [420]

Answer:

400 J work is done BY the engine.

The internal energy of the gas is 620 J

Explanation:

The given information are;

The heat added to the cylinder = 620 J

The force applied by the piston of the engine = 8.0 kN = 8,000 N

The distance over which the force moves (the piston) = 5.0 cm = 0.05 m

The work done (by the engine) = Force × Distance = 8,000 N × 0.05 m = 400 J

The internal energy is the sum of the kinetic and potential energy of the system

Therefore, given that the internal energy, U, is the sum total of the energy in the system

∴ U = The heat supplied to the system = 620 J

Which gives;

400 J work is done BY the engine.

The internal energy of the gas is 620 J.

6 0

3 years ago

Mohammad has been saving 8 each week. Today he spent 142 of the savings, and he now has 50 left. For how many weeks has he been

poizon [28]

Answer:

24 weeks

Explanation:

142+50=192

192/8=24

3 0

3 years ago

You attach a 2.90 kg mass to a horizontal spring that is fixed at one end. You pull the mass until the spring is stretched by 0.

Murljashka [212]

Answer:

Explanation:

The spring is stretched by .5 m and then released that means its amplitude of oscillation A is 0.5 m .

A = 0.5 m

After the release at one extreme point , the mass comes to rest again at another extreme point after half the time period ie

T / 2 = .3 s

T = 0.6 s

Angular velocity

ω = $\frac{2\times \pi}{T}$

ω = $\frac{2\times \pi}{0.6}$

ω = 10.45

Maximum velocity = ω A

ω and A are angular velocity and amplitude of oscillation.

Maximum velocity = 10.45 x .5

= 5.23 m /s

7 0

3 years ago

A newspaper article says that on the average, college freshmen spend 7.5 hours a week going to parties.14 One administrator does

Zielflug [23.3K]

Answer:

a.

The hypothesis Null and alternative can be formulate as a :

H0 = μ = 7.5 hr / week

Hₐ = μ < 7.5 hr / week

b.

The Null hypothesis is true and the administrator believes that the college freshman dot not spend 7.5 hours

E(x) = μ = 7.5 hr / week

SE (x) = σ / √ n = 9 / √100

SE (x) = 0.9

Z' = 6.6 - 7.5 / SE

Z' = 6.6 -7.5 / 0.9 = -1

The empirical rule in this case is use

% = (100 - 68 ) / 2 = 16%

c.

There is not strong arguments of Null Hypothesis so can be accept the H0 and is no significantly different from the report of 7.5 hr / week

5 0

3 years ago