Where should the tip of the thermometer be placed in a microscale distillation set up?

At or slightly below the side arm of the distillation head.

What are the concerns presented by overheating a distillation to a dry flask?

- the empty glassware might heat quickly, igniting vapors from the distillation

- the remaining solid residue might contain explosive peroxides

When performing the acid-catalyzed dehydration of an alcohol, the yield of product can be increased by ___________________ during the reaction.

distilling off the product

The dehydration is ______________, and removing the product from _________________ reduces the ___________ reaction.

reversible, the reaction flask, hydration

Why does the dehydration of an alcohol more often use concentrated sulfuric acid, H2SO4, as the acid catalyst rather than dilute hydrochloric acid, HCl?

- The presence of the chloride ion could result in a competing substitution

- The additional water solvent from a dilute solution could reverse the dehydration.

Which changes can be made to a chemical reaction in order to increase the rate constant?

Add a catalyst, increase the temperature

Suppose you are performing a titration, at the beginning of the titration you read the titrant volume as 2.03 mL. After running the titration and reaching the endpoint, you read the titrant volume as 20.03 mL. What volume, in ML, of titrant was required for the titration

18.0 mL

For a reaction rate based on one reactant, identify the type of graph that will give a linear plot in each case.

first-order reaction __________________

zero order reaction __________________

second order reaction ______________

In[reactant] versus time

[reactant] versus time

1/[recatant] versus time

Concnetration data is commonly monitored duringa reaction to determine the order with respect to a reactant. Consider the types of observations listed, and determine which order is likely for that reactant. Assume all other factors are held constant.

The reaction rate is constant regardless of the amount of reactant in solution. ______________________

The reaction rate increases in direct proportion to the concentration of the reactant in solution. _________________

An increase in the concentration of the reactant in solution causes the reaction rate to increase exponentially.

zero order, first order, second order

The term SN1 describes a reaction that is a(n) __________________ involving _______________________________________

nucleophilic substitution, one molecule in the rate determining step

If the dehydration reaction of an alcohol is successful, what changes would be seen in the IR spectrum fro the product compared to the starting material?

- The disappearance of an O-H band from the starting material

- The disappearance of a C-O band from the starting material

-The addition of a C-C double bond band in the product

In the presence of acid and heat, ______________________ will undergo a more effective dehydration reaction because it is a _____________ alcohol and the ________ in the intermediate of the mechanism will be more stable.

cyclohexanol, secondary, cation

Describe the complete role of the acid catalyst in the dehydration of an alcohol.

The acid protonates the hydroxyl group and then the conjugate base deprotonates an adjacent carbon

How can a catalyst be recognized in a mechanism?

The catalyst is used and then regenerated in a later step

The dehydration of a secondary alcohol, like cyclohexanol, is a mechanism that occurs ____________________. First, the alcohol is protonated to _______________________________, creating ___________ intermediate. Then, a _________________ is removed, moving the electrons from that bond to make a __________________

in two steps, leave as a water molecule, a cation, hydrogen ion, carbon-carbon double

Why is potassium hydroxide preferred over sodium hydroxide in organic reactions?

Potassium hydroxide is more soluble in organic alcohols

Identify the best description of the role each species play in the SN2 synthesis of nerolin

I- ______________________

KOH ____________________

I-CH2CH3 ___________________

(two rings w/ one O-) _____________

leaving group, base, electrophile, nucleophile

Identify the best description of the role each species play in the SN2 synthesis of nerolin

_____________________

product

Consider the SN2 reaction of an alcohol with an alkyl halide in the presence of base.

The ______ should be added to the alcohol first to _____________ the alcohol and allow it to attack the ______________

base, deprotonate, alkyl halide

An SN2 reaction is a type of ______________________ in which the nucleophile attacks the electrophile ____________________ a leaving group leaves.

The rate of the reaction depends on the concentration of _______________

substitution reaction, at the same time, both reactants

When working in a fume hood, what is the best position of the hood sash?

As low as possible no more than halfway up

When working in the fume hood, it is important to make an effort to minimize __________. Only keep items in the fume hood if they are being used for ________________. Do not _______ chemicals in the fume hood unless instructed to do so.

clutter, the current experiment, store

If crystal growth does not start on its own after the solution in the flask returns to room temperature, identify the best way to promote its process.

Add a bit of solid as a seed crystal, scratch the bottom of the flask gently with a stirring rod.

When should you start timing the reflux for the procedure?

when the reflux ring stabilizes in the condenser

When it is time to end a reflux, first _______________________ and then turn off the heat. ____________________________ until the system has cooled.

lower the heat source, leave the condenser water on

The biggest concern of working with hydrocarbons in lab is that many of them are _____________

Therefore, hydrocarbons should be handled _____________ to contain any associated vapors with that hazard

flammable, in the hood

Bayer's test, also known as the permanganate test, shows the presence of _______________

a positive bayers test appears as _____________

a negative bayers test appears as ______________

alkenes, a brown precipitate, a purple solution

Consider the reaction of bromine with the pictured alkene

Which structure shows the correct bonding for the product?

The bromine test shows the presence of ____________

A positive bromine test appears as a _____________

A negative bromine test as ____________________

alkenes, a colorless solution, an orange solution

In general, when hydrocarbons like oil are added to water, the two liquids ______________ because hydrocarbons are ____________ and water is ___________

do not mix, non polar, polar

In general, when a hydrocarbon is added to water, the hydrocarbon will _________ the water because hydrocarbons are _______ than water

float above, less dense

A hydrocarbon is saturated if _________________________ are present.

_______________ are saturated hydrocarbons

A hydrocarbon is unsaturated if _____________________ are present.

_________________ are unsaturated hydrocarbons

only single bonds

Alkanes

any multiple bonds

Alkenes

Identify the type of hydrocarbon represented by each structure

Alkyne (unsaturated)

Identify the type of hydrocarbon represented by each structure

Aromatic (unsaturated)

Identify the type of hydrocarbon represented by each structure

Alkane (saturated)