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2 years ago

Why is cathode positive in leclanche cell??

Physics

1 answer:

laila [671]2 years ago

7 0

Answer:

Because the zinc is reluctant

Explanation:

A leclanche cell contains a conducting solution (electrolyte) of ammonium chloride, a cathode (positive terminal) of carbon, a depolarizer of manganese dioxide (oxidizer), and an anode (negative terminal) of zinc (reductant).

As the Zn2+ ions move away from the anode, leaving their electrons on its surface,

Zn → Zn2+ + 2e−

the anode becomes more negatively charged than the cathode. When the cell is connected to an external electrical circuit, the excess electrons on the zinc anode flow through the circuit to the carbon rod, the movement of electrons forming an electric current.

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Consider a sample of helium gas in a container fitted with a piston, as pictured below. The piston is frictionless, but has a ma

andrezito [222]

Question:

Consider a sample of helium gas in a container fitted with a piston as pictured below. The piston is frictionless, but has a mass of 10.0 kg. How many of the following processes will cause the piston to move away from the base and decrease the pressure of the gas? Assume ideal behavior.

I. Heating the helium. II.

II. toRemoving some of the helium from the container.

III. Turning the container on its side.

IV. Decreasing the pressure outside the container.

a) 0

b) 1

c) 2

d) 3

e) 4

Answer:

Only one process will cause the piston to move which is

i) Heating the helium

Explanation:

When helium is heated it becomes less dense or lighter. Heating the helium will cause an increase in volume which will make the piston to move away from the base. When the volume finishes increasing, the piston will stop moving which in turn will make the forces on both sides of the piston balanced, so the pressure inside will balance the weight of the piston and that of the atmosphere. From that we can see that there has been a pressure change as a result of heating.

6 0

3 years ago

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A toy car accelerates at a constant rate from rest to a speed of 4 m/s in a time of 0.55 s. What was the magnitude of the accele

Korvikt [17]

initial velocity=u=0m/s
Final velocity=v=4m/s
Time=t=0.5s

$\\ \sf\longmapsto Acceleration=\dfrac{v-u}{t}$

$\\ \sf\longmapsto Acceleration=\dfrac{4-0}{0.5}$

$\\ \sf\longmapsto Acceleration=\dfrac{4}{0.5}$

$\\ \sf\longmapsto Acceleration=8m/s^2$

3 0

2 years ago

Describe and explain the motion of a small ball floating on a pond when waves travel across the pond

laila [671]

I think the answer is periodic motion.

4 0

2 years ago

Two moles of helium are initially at a temperature of 21.0 ∘Cand occupy a volume of 3.30×10−2 m3 . The helium first expands at c

Anettt [7]

Answer:

(B) The total internal energy of the helium is 4888.6 Joules

(D) The final volume of the helium is 0.066 cubic meter

Explanation:

(B) ∆U = P(V2 - V1)

From ideal gas equation, PV = nRT

T1 = 21°C = 294K, V1 = 0.033m^3, n = 2moles, V2 = 2× 0.033=0.066m^3

P = nRT ÷ V = (2×8.314×294) ÷ 0.033 = 148140.4 Pascal

∆U = 148140.4(0.066 - 0.033) = 4888.6 Joules

Assuming a closed system

(C) Wc = (P1V1 - P2V2) ÷ 0.4 = (148140.4×0.033 - 56134.7×0.066) ÷ 0.4 = (4888.6 - 3704.9) ÷ 0.4 = 1183.7 ÷ 0.4 = 2959.25 Joules

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3 years ago

a pumpkin with a mass of 2.5 kg was pushed toward a wall the average acceleration of the pumpkin was 10.7 miles per second squar

Sati [7]

Alright, to begin with. The unit of Force is in Newtons. Meaning the first two options are out of the answers. Now in order to find the force. You will need to take the mass and multiply that by the acceleration. Which will give you 26.75 Newtons.

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3 years ago

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