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4 years ago

14

What unit is similar to light year

1 answer:

Sidana [21]4 years ago

8 0

You could use miles
one light year equals 6 trillion miles

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I know the answer but what type of energy is this.

k0ka [10]

Answer:

Elastic potential energy

Explanation:

7 0

3 years ago

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A galvanic cell based on these half-reactions is set up under standard conditions where each solutions is 1.00 L and each electr

Marat540 [252]

Complete Question

$Fe^{2+} + 2e^-----> Fe \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ E^0_{red} = - 0.441 V$

$Cd^{2+} + 2e^- -----> Cd \ \ \ \ \ \ \ \ \ \ \ \ \ \ E^0_{red} = -0.403V$

A galvanic cell based on these half-reactions is set up under standard conditions where each solutions is 1.00 L and each electrode weighs exactly 100.0 g. How much will the Cd electrode weigh when the non-standard potential of the cell is 0.03305 V?

Answer:

The mass is M= 117.37g

Explanation:

The overall reaction is as follows

$Cd^{2+} + Fe Fe^{2+} + Cd$

The reaction is this way because the potential of $Cd^{2+} \ reducing \ to \ Cd$ is higher than the potential of $Fe^{2+} \ reducing \ to \ Fe$ so the the Fe would be oxidized and $Cd^{2+}$ would be reduced

At equilibrium the rate constant of the reaction is

$Q = \frac{concentration \ of \ product }{concentration \ of reactant }$

$= \frac{[Fe^{2+}[Cd]]}{[Cd^{2+}][Fe]}$

The Voltage of the cell $E_{cell} = E_{Cd^{2+}/Cd } + E_{Fe^{2+} /Fe}$

Substituting the given values into the equation

$E_{cell} = -0.403 -(-0.441)$

$= 0.038V$

The voltage of the cell at any point can be calculated using the equation

$E = E_{cell} - \frac{0.059}{n_e} Q$

Where $n_e \ is \ the \ number\ of\ electron$

Substituting for Q

$E = E_{cell} - \frac{0.059}{n_e} \frac{[Fe^{2+}[Cd]]}{[Cd^{2+}][Fe]}$

When E = 0.03305 V

$E = E_{cell} - \frac{0.59}{n_e} \frac{Fe^{2+}}{Cd^{2+}}$

Since we are considering the Cd electrode the equation becomes

$E= E_{cell} - \frac{0.059}{n_e} [\frac{1}{Cd^{2+}} ]$

Substituting values and making [ $Cd^{2+}$ ] the subject

$[Cd^{2+}] =\frac{1}{e^{[\frac{0.03305- 0.038}{\frac{0.059 }{2} }] }}$

$= 0.8455M$

Given from the question that the volume is 1 Liter

The number of mole = concentration * volume

= 0.8455 * 1

= 0.8455 moles

At the standard state the concentration of $Cd^{2+}$ is =1 mole /L

Hence the amount deposited on the Cd electrode would be

= Original amount - The calculated amount

= 1 - 0.8455

= 0.1545 moles

The mass deposited is mathematically represented as

$mass = mole * molar \ mass$

The Molar mass of Cd $= 112.41 g/mol$

Mass $= 0.1545 *112.41$

$= 17.37g$

Hence the total mass of the electrode is = standard mass + calculated mass

M= 100+ 17.37

M= 117.37g

6 0

3 years ago

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8. Give the net force for the following:

olya-2409 [2.1K]

Answer:

i think it's is 30N

Explanation:

i got it right

8 0

3 years ago

If spring has a spring constant of 500 N/m and is stretched .50 meters,how much energy is stored in the spring ((show work for f

Free_Kalibri [48]

Answer:

The energy stored is: 62.5 Joules

Explanation:

Given

$k = 500N/m$ --- spring constant

$x = 0.5m$ --- stretch

Required

The amount of energy

This is calculated as:

$U = \frac{1}{2} kx^2$

$U = \frac{1}{2} * 500N/m * (0.5m)^2$

$U = 250N/m * (0.5m)^2$

$U = 62.5\ J$

7 0

3 years ago

You can see yourself in the mirror because?

jok3333 [9.3K]

Mirrors reflect light waves.

3 0

3 years ago

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