Answer:
It obeys rule
Explanation:
Benzene is an aromatic hydrocarbon because it obeys Hückel's rule.
Answer:
The reaction isn't yet at equilibrium. The overall reaction will continue to move in the direction of the products.
Assumption: this system is currently at
.
Explanation:
One way to tell whether a system is at its equilibrium is to compare its reaction quotient
with the equilibrium constant
of the reaction.
The equation for
is quite similar to that for
. The difference between the two is that
requires equilibrium concentrations, while
can be calculated even when the system is on its way to equilibrium.
For this reaction,
.
Given these concentrations,
.
The question states that at
,
. Assume that currently this system is also at
. (The two temperatures need to be the same since the value of
depends on the temperature.)
It turns out that
. What does this mean?
- First, the system isn't at equilibrium.
- Second, if there's no external changes, the system will continue to move towards the equilibrium. Temperature might change. However, eventually
will be equal to
, and the system will achieve equilibrium.
In which direction will the system move? At this moment,
. As time proceeds, the value of
will increase so that it could become equal to
. Recall that
is fraction.
When the value of
increases, either its numerator becomes larger or its denominator becomes smaller, or both will happen at the same time. However,
- Concentrations on the numerator of
are those of the products; - Concentrations on the denominator of
are those of the reactants.
As time proceeds,
- the concentration of the products will increase, while
- the concentration of the reactants will decrease.
In other words, the equilibrium will move towards the products.
<span>Safety glasses are to be worn whenever working with acids, bases, or any flammable materials. Let the instructor know immediately about any glassware breakage or chemical spills that may occur so that proper cleanup procedures can be instituted.Use pipet fillers whenever pipeting any fluid.Whenever working with acids or bases, have the chemicals available at your work station, do not carry pipets with fluid across the room.When diluting acids, pour the acid into the water, NOT water into acid as this may cause spattering of the acid.When acid is mixed with another reagent, an exothermic reaction may occur which heats up the container, This is natural, so do not panic and spill contents.All volatile materials must be handled in a hood with the exhaust fan on.When refluxing any solutions, perform this operation under a hood, and use boiling beads in the reflux vessel to prevent any excessive "bumping" and possible glass breakage.Use heat-resistant gloves and/or tongs when handling hot glassware, chinaware, etc.Use plastic gloves when handling any hazardous materials to prevent skin contact.Label and date all chemical mixtures that are made up and kept for future use.Do not store basic solutions in glass containers with glass stoppers, use plastic or rubber stoppers.Dispose of all used solutions in an approved manner as directed by the instructor.Empty all used inoculated bacteriological media from test tubes or dishes into a designated container so that it may be sterilized before disposal.Before leaving, turn off all power and heat to the apparatus you have used, or place in the standby mode.Clean all spatulas, glassware, and dishes after use and before storage to prevent contamination.<span>Return all chemicals you are using to their proper storage space.Be familiar with the use of the eye-wash, the laboratory shower (if equipped), and the first-aid kit if they are needed at any time.</span></span>
"any of a large class of chemical compounds in which one or more atoms of carbon are covalently linked to atoms of other elements, most commonly hydrogen, oxygen, or nitrogen. The few carbon-containing compounds not classified as organic include carbides, carbonates, and cyanides. See chemical compound."