The biochemistry that takes place inside cells depends on various elements, such as sodium, potassium, and calcium, that are dissolved in water as ions. These ions enter cells through narrow pores in the cell membrane known as ion channels. Each ion channel, which is formed from a specialized protein molecule, is selective for one type of ion. Measurements with microelectrodes have shown that a 0.30-nm-diameter potassium ion (K+) channel carries a current of 1.8 pA. How many potassium ions pass through if the ion channel opens for 1.0 ms?

The biochemistry that takes place inside cells depends on various elements, such as sodium, potassium, and calcium, that are dissolved in water as ions. These ions enter cells through narrow pores in the cell membrane known as ion channels. Each ion channel, which is formed from a specialized protein molecule, is selective for one type of ion. Measurements with microelectrodes have shown that a 0.30-nm-diameter potassium ion (K+) channel carries a current of 1.8 pA. How many potassium ions pass through if the ion channel opens for 1.0 ms?

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter21: Potentiometry

Section: Chapter Questions

Problem 21.23QAP

See similar textbooks

Similar questions

What mass of iron (III) sulfate is present in 100 cm3 of the solution used to measure the standard electrode potential of this cell?
Gold is frequently purified by electroplating. Typically the gold is dissolved in a cyanide solution (which is fairly selective for gold) and then it is pulled out of solution by electroplating. If the electroplating apparatus used a current of 3.5 amperes, then how long will it take (hr) to purify one ounce of gold from a gold(III) cyanide solution?
How many electrons or protons are transported through the double layer per second for each of the electrodes Cu,H2|H+ and Pt|Ce4+,Ce3+ when they are at equilibrium at 25 °C? Take the area as 1.0 cm2 in each case. Estimate the number of times each second a single atom on the surface takes part in an electron transfer event, assuming an electrode atom occupies about (260 pm)2 of the surface.
Why is it not possible to measure single electrode potential?
A fuel cell develops an electric potential from the chemical reaction between reagents supplied from an outside source. What is the potential of a cell fuelled by (a) hydrogen and oxygen, (b) the complete oxidation of benzene at 10 bar and 298 K?
The standard cell potential of a Daniell cell, with cell reactionZn(s) + Cu2+(aq) → Zn2+(aq) + Cu(s), is 1.10 V at 25 °C.Calculate the corresponding standard reaction Gibbs energy.
From the biological standard half-cell potentialsE⊕(O2,H+,H2O) = +0.82 V and E⊕(NADH+,H+,NADH) = -0.32 V, calculate the standard potential arising from the reaction in which NADH is oxidized to NAD+ and the corresponding biological standard reaction Gibbs energy.
The exchange current density at the electrode Pt| Fe3+| Fe2+ is 2.4 x 10-3 A cm-2, How many electrons are transported through the double layer per second in the cell (area of 1 cm2 each)? Estimate the number of times per second that a single atom on the surface takes part in an electron transfer event, assuming that the atom occupies 280 pm2 of the surface of the electrode
The chemical potential of a particular substance in the region A of a system is 5kJ higher than potential of this substance in region B. By how much does the Gibbs energy of the system change when 2mmol of the substance is transferred from region A to region B? Will this transfer be spontaneous?
The standard potential of a Daniell cell, with cell reaction Zn(s) + Cu2+(aq) → Zn2+(aq) + Cu(s), is 1.10 V at 25 °C. Calculate the corresponding standard reaction Gibbs energy.
What the standard potential of an electrode of a cell containing the Sn²⁺/Sn and Br₂/Br⁻¹ couples?
In the electroplating of nickel from a solution containing Ni2+ ions what weight of nickel-metal will be produced at the cathode by a current of 4.02 A flowing for 100 min?