Which of the following is a result of the greenhouse effect?

Potassium thiocyanate, KSCN, is often used to detect the presence of Fe3+ ions in solution through the formation of the red Fe(H

Natalija [7]

Answer:

Ferric ions left in the solution at equilibrium is $8.0\times 10^{-6} M$ .

Explanation:

Moles of ferric nitrate in 0.700 L = n

Volume of the solution = V = 0.700 L

Molarity of ferric nitrate = M = 0.00150 M

$n=M\times V=0.00150 M\times 0.700 L=0.00105 mol$

Moles of potassium thiocyanate in 0.700 L = n'

Volume of the potassium thiocyanate solution = V' = 0.700 L

Molarity of potassium thiocyanate = M' = 0.200 M

$n'=M'\times V'=0.200 M\times 0.700 L=0.140 mol$

Molarity of ferric ions after mixing :

1 mol of ferric nitrate gives 1 mol of ferric ions.Then 0.00105 mol ferric nitrate will :

Moles of ferric ions = 0.00105 mol

$M_1=\frac{0.00105 mol}{0.700 L+0.700 L}=0.00075 M$

Molarity of thiocyanate ions after mixing :

1 mol of potassium thiocyanate gives 1 mol of thiocyanate ions.Then 0.140 mol potassium thiocyanate will give:

Moles of thiocyanate ions = 0.140 mol

$M_2=\frac{0.140 mol}{0.700 L+0.700 L}=0.1 M$

Complex equation:

$Fe^{3+}+SCN^-\rightleftharpoons [Fe(SCN)]^{2+}$

0.00075 M 0.1 M 0

At equilibrium:

(0.00075 M -x) (0.1 M-x) x

The formation constant of the given complex = $K_f=8.9\times 10^2$

$K_f=\frac{[[Fe(SCN)]^{2+}]}{[[Fe^{3+}]][SCN^{-}]}$

$8.9\times 10^2=\frac{x}{(0.00075 M -x)\times (0.1 M-x)}$

Solving for x:

x = 0.000742 M

Ferric ions left in the solution at equilibrium :

= (0.00075 M -x) = (0.00075 M - 0.000742 M)= $8.0\times 10^{-6} M$

5 0

3 years ago

As a storm from moves in, you notice that a column of mercury in a barometer rises to 736 mm. (a) Determine the air pressure. (b

sesenic [268]

Answer:

The air pressure is 9.8 *10^4 pa

The water will rise to a height of 10.0 meter

Explanation:

Step 1: Data given

As a storm from moves in, you notice that a column of mercury in a barometer rises to 736 mm.

Step 2: Calculate the air pressure

The Pressure against the mercury column = h*d*g = 0.736 * 13593 * 9.81 = 9.8 * 10^4 Pa

Step 3: Calculate the height of the water

Let the Pressure the water column for same pressure is h meter : -

9.8 * 10^4 = h*d*g

=>9.8*10^4 = h*1000*9.81

=>h = 10.0 meter

The water will rise to a height of 10.0 meter

5 0

3 years ago

HELPPPPPP MEEEE‼️‼️‼️Use the equations from

Step2247 [10]

1.180
2.-900
3.20
4.8
Hope this helps

8 0

3 years ago

In which of Piaget’s stages would a child be if the child has just developed object permanence?

rodikova [14]

Answer:

preoperational

Explanation:

7 0

3 years ago

Read 2 more answers

For a first-order reaction, A → B, the rate coefficient was found to be 3.4 × 10-4 s-1 at 23 °C. After 5.0 h, the concentration

Illusion [34]

Answer:

the original concentration of A = 0.0817092 M

Explanation:

A reaction is considered to be of first order it it strictly obeys the graphical equation method.

$k_1 = \dfrac{2.303}{t}log \dfrac{a}{a-x}$

where;

k = the specific rate coefficient = 3.4 × 10⁻⁴ s⁻¹

t = time = 5.0 h = 5.0 × 3600 = 18000 seconds

a = initial concentration = ???

a - x = remaining concentration of initial concentration at time t = 0.00018 mol L⁻¹

$3.4 \times 10^{-4}= \dfrac{2.303}{18000}log \dfrac{a}{0.00018}$

$3.4 \times 10^{-4}= 1.27944 \times 10^{-4} \times log \dfrac{a}{0.00018}$

$\dfrac{3.4 \times 10^{-4}}{1.27944 \times 10^{-4}}= log \dfrac{a}{0.00018}$

$2.657= log \dfrac{a}{0.00018}$

$10^{2.657}= \dfrac{a}{0.00018}$

$453.94 = \dfrac{a}{0.00018}$

$a =453.94 \times 0.00018$

a = 0.0817092 M

Thus , the original concentration of A = 0.0817092 M

8 0

3 years ago