For each of the reactions at constant pressure, determine whether the system does work on the surroundings, the surroundings does work on the system, or essentially no work is performed.

(a) 4Fe + 3O2 --> 2Fe2O3
(b) 2H2O2 --> O2 + 2H2O

Explanation:

When work is done then there will occur change in volume. And, most change in volume occurs when there will be production of gas is taking place. We assume that no work is done when no gas is produced.

(a)   For

Here, 3 moles of gas is producing 0 moles of gas. This means that work is done on the system.

(b)  And, more is the production of a gas taking place in a reaction more will be the amount of work done by the system.

For

Here, 2 moles of a gas is producing 3 moles of a gas. Since, gas is increasing so, work will be done by the system.

pure water does not conduct electricity very well. however, when certain substances are dissolved in water, the solution does conduct electricity. you can make a simple device that shows how well a solution conducts electricity. this device uses a flashlight bulb to indicate how well the solution conducts electricity. the better the solution conducts electricity, the brighter the bulb will glow.

explanation:

pie chart because it is in percents ( % )