How does increasing concentration affect emf?
In general, if the concentrations of reactants increase relative to those of products, the cell reaction becomes more spontaneous and the emf increases. Conversely, if the concentrations of products increase relative to reactants, the emf decreases.
Does emf of cell depend on concentration?
Concept: The emf of a cell depends on the concentrations of ion and on gas pressures. Nernst equation relates the cell emf’s for various concentrations and gas pressures to standard electrode potentials.
How do you increase the emf of a cell?
Daniel cell, the EMF of the cell can b e increased b y
- A. increasing the concentration of Zn2+ ions.
- B. increasing the concentration of Cu2+ ions.
- C. increasing the concentration of Cu2+ ions.
- decreasing the concentration of Zn2+ ions.
Why does the emf of the cell change with concentration of solution?
Changing the concentration in the cell of one solution would increase the cell’s voltage potential as you bring the device further out of equilibrium. Since the concentration on only one side of the cell has increased, the gradient of concentration is steeper across both sides of the cell.
What affects the EMF of a cell?
Factors affecting e.m.f. E.m.f. of a cell depends upon the material of electrodes and electrolyte used in the cell. It is independent of shape of electrodes, distance between electrodes and the amount of electrolyte.
Why the emf of a concentration cell gradually decreases?
Answer: Conversely, if the concentrations of products increase relative to reactants, the emf decreases. As voltaic cell operates, reactants are converted into products, which increases the value of Q and causes the emf to decrease.
What affects the emf of a cell?
What is emf of cell on what factors does it depend?
The e.m.f. of different cell depends on the following factors: (i) The material of the electrodes. (ii) The electrolyte used in the cell. It is to be noted that the e.m.f. of a cell does not depend on its shape or size.
What will be the EMF of the cell?
The electromotive force (EMF) is the maximum potential difference between two electrodes of a galvanic or voltaic cell. If the cell potential is negative, the reaction is reversed. In this case, the electrode of the galvanic cell should be written in a reversed order.
Why does the EMF of a cell change when a current flows?
The pressure change depends on the mechanical details of the pump. In an electrical circuit the pressure is the electrical potential, so in a battery electrons flow in at low potential and flow out at high potential. Both of these will slightly change the EMF you measure when you connect your voltmeter to the battery.
Why does EMF decrease over time?
There is a decrease in the electric potential in the battery due to the internal resistance. The potential decreases due to the internal resistance −Ir, making the terminal voltage of the battery equal to (ϵ−Ir). The voltage then decreases by (IR).
What are the factors that affect the induced emf?
The induced emf is directly proportional to the number of turns, magnetic field, area and the time in which the magnetic flux changes. Therefore, the magnitude of the induced emf depends on the change in magnetic flux and also on the time in which the magnetic flux changes.
What happens to the EMF when you change the anodic concentration?
The answer depends upon the type of EMF you are treating with like if you are using a Mercury cell (button cell ,common in wristwatch) the EMF remain unchanged by changing the anodic concentration because if you write the Nernst equation u can see that the EMF of the cell is independent of concentration .
What happens to the EMF when the reactants are used up?
The EMF of the cell will fall as the reactants are used up and products increase in concentration. At equilibrium concentrations of reactants and products, the EMF = 0, as there is a NET 0 movement in the same way that even if two equal and opposite forces are acting, still the net force remains zero as their effect cancels out.
How to calculate the cell potential or emf of electrochemical cell?
The cell potential or EMF of the electrochemical cell can be calculated by taking the values of electrode potentials of the two half – cells. There are usually three methods that can be used for the calculation: By taking into account the oxidation potential of anode and reduction potential of cathode.
What does the electrode potential of an electrochemical depend on?
So the electrode potential of an electrochemical depends on the standard electrode potential, temperature, no. of electrons involved in the chemical reaction and the concentration of the reacting species. Students understand the terms, electrochemical cell, electrolytic cell, Daniell cell, salt bridge, EMF.