Different Concentrations of Ions on Either Side of a Cell $\rightarrow$

question 79

Multiple Choice

Different concentrations of ions on either side of a cell membrane constitute a concentration cell, which is described by the Nernst equation given below.A cell must expend energy to maintain this concentration gradient by moving ions from one side of the membrane to the other.How much energy must be expended to transport 1 mole of sodium ions across a membrane when the sodium ion concentration is 0.10 M on one side of the membrane and 0.010 M on the other side, and the temperature is 37°C body temperature) ? Assume that the potential across the membrane is -70 mV. (Given: Na⁺ +e^- $\rightarrow$ Na, Eº_red = -2.71 V; =96,485 C; 1 J = 1 C V; R = 8.315 J / mol K) )
E = E° - InQ

• A)50 kJ
• B)260 kJ
• C)6.0 kJ
• D)250 kJ
• E)6,000 kJ

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Definitions:

Binding Price Ceiling

A legally established maximum price for goods or services that is below the market equilibrium price, leading to shortages.

Binding Price Floor

A government or regulatory-imposed price control that sets a minimum price for a good or service, potentially leading to excess supply if set above the equilibrium price.

Market Demand

The total quantity of a good or service that all consumers in a market are willing and able to purchase at various prices during a specified period.

Binding Price Floor

A government or regulatory-imposed price control that sets the minimum price that can be charged for a good or service, above the equilibrium price, leading to potential surpluses.