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Electrochemistry - Equilibrium

Ipatiy [6.2K]

Answer:

Explanation:

The relation between equilibrium constant and Ecell is given below .

E⁰cell = (RT / nF ) lnK , F is faraday constant T is 273 + 25 = 298 K

E⁰cell = 1.46 - 1.21 = .25 V

n = 2

Putting the values

.25 = (8.314 x 298 lnK) / (2 x 96485 )

lnK = 19.47

K = 2.85 x 10⁸

2 )

Change in free energy Δ G

Δ G ⁰ = nE⁰ F

n = 4

E⁰ = .4 + .83 = 1.23 V

Δ G ⁰= 4 x 1.23 x 96485

= 474706 J / mol

3 )

E⁰cell = (RT / nF ) lnK

n = 2

1.78 = 8.314 x 298 lnK / 2 x 96485

lnK = 138.638

K = 1.62 x 10⁶⁰

8 0

3 years ago

How many moles of hcl are required to neutralize aqueous solutions of these bases:

Lemur [1.5K]

The answers are a.) 0.03 mol KOH requires 0.03 mol HCl, b.) 2 mol NH3 requires 2 mol HCl and c.) 0.1 mol Ca(OH)2 requires 0.2 mol HCl.
Solution:
We need to write the balanced equations for each reactions to find out the stoichiometry for each reactants.
a.) HCl (aq) + KOH (aq) → KCl (aq) + H2O(ℓ)
From the balanced equations, we can see that 1 HCl reacts with 1 KOH, therefore if 0.03 mol KOH is reacted then 0.03 mol HCl must also be present.

b.) HCl(aq) + NH3(aq) ) → NH4Cl(aq)
If 2 moles of NH3 are reacted then 2 moles of HCl must also be present since 1 HCl reacts with 1 NH3 from the balanced reaction.

c.) 2HCl(aq) + Ca(OH)2(s) → CaCl2(aq) + 2H2O(ℓ)
We can see that 2 HCl react with 1 Ca(OH)2, hence if 0.1 mol of Ca(OH)2 is reacted then 0.2 mol HCl must also be present.

8 0

3 years ago

Read 2 more answers

Which subatomic particle is used to identify an element and is unique to that element?

Yuki888 [10]

Protons because each element has a different number. Example, Oxygen has 8, Nitrogen has 7, Carbon has 6, etc.

3 0

3 years ago

Boyle's Law states that when a sample of gas is compressed at a constant temperature, the pressure P and volume V satisfy the eq

____ [38]

Answer:

The gas is decreasing at a rate of 50 cubic centimeters per minute.

Explanation:

The Boyle's Law is represented by the following expression:

$P\cdot V = k$ (1)

Where:

$P$ - Pressure, in kilopascals.

$V$ - Volume, in cubic centimeters.

$k$ - Proportionality constant, in kilopascal-cubic centimeters.

By definitions of rate of change and implicit differentiation, we derive the following differential equation:

$\dot P \cdot V + P\cdot \dot V = 0$ (2)

Where:

$\dot P$ - Rate of change of the pressure, in kilopascals per minute.

$\dot V$ - Rate of change of the volume, in cubic centimeters per minute.

Then, we clear the rate of change of the volume within (2):

$P\cdot \dot V = -\dot P\cdot V$

$\dot V = -\left(\frac{\dot P}{P} \right) \cdot V$

If we know that $P = 180\,kPa$ , $\dot P = 30\,\frac{kPa}{min}$ and $V = 300\,cm^{3}$ , then the rate of change of the volume is:

$\dot V = -\left(\frac{\dot P}{P} \right) \cdot V$

$\dot V = -50\,\frac{cm^{3}}{min}$

The gas is decreasing at a rate of 50 cubic centimeters per minute.

3 0

3 years ago

17. The correct arrangement of the following elements in order of

tatuchka [14]

Answer:

Got your back

Explanation:

If the ions derived from different atoms are isoelectronic species, then they all have same number of electrons in their electronic shells and will have got same electronic configuration but their nuclear charge will differ because of their difference in number of protons in the nucleus. With increase in number of protons in the nucleus the electrons are more attracted towards nucleus thereby causing the decrease in ionic radius. On this principle our problem will be solved

The given ions are

7N-3

→no. of proton

=7

and

no of electron

=10

8O-2

→

no. of proton

=8

and

no of electron

=10

9F-→

no. of proton=9

and no of electron=10

11Na→

no. of proton=11

and no of electron=10

12 Mg-3→

no. of proton=12 and

no of electron=10

Hence the increasing order of ionic radius is

12Mg-3<11Na+<9F-<8O-2<7N-3

To rmember ->For isoelectronic species lower the nuclear charge higher the radius

8 0

3 years ago