Chemistry

The atom

It is an acidic solution.

Aluminum is reduced.

Zinc ions are formed.

Molarity = moles of solute/Liters of solution

3.42 M NaOH = 1.3 moles NaOH/Liters NaOH

Liters NaOH = 1.3 moles NaOH/3.42 M NaOH

= 0.38 Liters

The reduction half-reaction of a redox reaction

. The reaction will be spontaneous.

When a potential difference is applied across the electrodes, one becomes positive (the anode) and one negative.(the cathode). Ions in the electrolyte are attracted to the electrodes, and move towards them. Here they are discharged, resulting in chemical changes. At the anode, negative ions give up their electrons, and at the cathode positive ions receive electrons, which maintains a flow of electrons (a current) in the external circuit. The electrolyte may be molten, or a solution. For instance, in molten sodium chloride, positive sodium ions move to the cathode where they accept electrons and become sodium atoms, i.e. sodium metal is formed. At the same time, negative chloride ions move to the anode and lose electrons, forming chlorine atoms, which combine to make chlorine molecules, and chlorine gas is evolved.

Periodic trends illustrate how some elements are very reactive while others are stable.

The metal being used as the cathode

A Spontaneous Redox Reaction

Nose

MgCl2 aq plus Zn s is the oxidation half-reaction for Mg s plus ZnCl2 aq.

The overall voltage for a redox reaction with the half reactions Mg s -- Mg2 plus plus 2e- and Cu2 plus -- Cu is 76 V.

A measure of the acidity of the solution