How did Thomson show that cathode rays are different from light?

Write Huckel's rule below and determine how many electrons are required to make an aromatic ring with n = 0, 1, and 2.

lisov135 [29]

Answer: The number of electrons for n = 0, 1 and 2 are 2, 6 and 10 respectively.

Explanation:

Huckel's rule is used to determine the aromaticity in a compound. The number of delocalized $\pi-$ electrons are calculated by using the equation:

$\text{Number of delocalized }\pi-\text{ electrons}=4n+2$

where,

n = 0 or any whole number

Calculating the value of electrons for n = 0

Putting values in above equation, we get:

$\text{Number of delocalized }\pi-\text{ electrons}=4(0)+2=2$

Calculating the value of electrons for n = 1

Putting values in above equation, we get:

$\text{Number of delocalized }\pi-\text{ electrons}=4(1)+2=6$

Calculating the value of electrons for n = 2

Putting values in above equation, we get:

$\text{Number of delocalized }\pi-\text{ electrons}=4(2)+2=10$

Hence, the number of electrons for n = 0, 1 and 2 are 2, 6 and 10 respectively.

4 0

3 years ago

Write a paragraph on: how Westfield how the rust in their water formed.

Mariana [72]

Answer:

Students have investigated what's going on in the fictional town of Westfield, they learned that the mysterious reddish-brown substance in the water is actually rust, which formed because of a chemical reaction between the iron pipes and the fertilizer substance in the water.

Explanation:

8 0

2 years ago

To titrate 45.00 milliliters of an unknown HCl sample, use 25.00 milliliters of a standard 0.2000 M NaOH titrant. What is the mo

gtnhenbr [62]

V ( HCl ) = 45.00 mL in liters : 45.00 / 1000 => 0.045 L

M ( HCl ) = ?

V ( NaOH ) = 25.00 / 1000 => 0.025 L

M ( NaOH) = 0.2000 M

number of moles NaOH :

n = M x V = 0.2000 x 0.025 => 0.005 moles of NaOH

Mole ratio:

HCl + NaOH = NaCl + H2O

1 mole HCl ---------- 1 mole NaOH
? mole HCl ---------- 0.005 moles NaOH

moles HCl = 0.005 x 1 / 1

= 0.005 moles of HCl :

M ( HCl ) = n / V

M ( HCl ) = 0.005 / 0.045

= 0.1111 M

hope this helps!

4 0

3 years ago

An iron ore sample weighing 0.5562 g is dissolved HCl (aq), and the iron is obtained as Fe2 in solution. This solution is then t

erik [133]

Answer:

$\% Fe^{+2}=70%$

Explanation:

Hello,

In this case, we could considering this as a redox titration:

$Fe^{+2}+(Cr_2O_7)^{-2}\rightarrow Fe^{+3}+Cr^{+3}$

Thus, the balance turns out (by adding both hydrogen ions and water):

$Fe^{+2}\rightarrow Fe^{+3}+1e^-\\(Cr_2^{+6}O_7)^{-2}+14H^++6e^-\rightarrow 2Cr^{+3}+7H_2O\\\\6Fe^{+2}+(Cr_2^{+6}O_7)^{-2}+14H^++6e^-\rightarrow Cr^{+3}+7H_2O+6Fe^{+3}+6e^-$