CHM2211L Progress Quiz 1

Hot gravity filtration is used in the process of recrystallization. Specifically, it is used to remove any insoluble impurities from the sample. It is good to use the stemless funnel for this technique because it prevents crystallization from occurring on the stem of the funnel (since stemless). To elaborate, if hot solution were to become stuck on the stem of the funnel, it may cool and therefore crystallize and obstruct/block the funnel stem.

Most polar = water Least polar = hexane Miscible = water and ethanol

Activated carbon is a form of carbon used as an absorbent and contains small, low-volume pores. In this experiment, activated carbon is used to remove the colored impurities from the sample; in general, activated carbon is used to purify and decolorize samples. Activated carbon is also known as "decolorizing carbon" or "activated charcoal."

One could determine if the routes are identical by mixing the samples yielded through experimentation and determining the melting point range. If the melting point range stays about the same, the synthetic routes are likely identical.

HCl is used instead of plain deionized water because HCl has the ability to protonate the amine group on p-phenetidine, forming a salt and making it easier to dissolve.

The purpose of the sodium acetate solution in the amide synthesis of acetophenetidin is that is acts as a buffer in the reaction so that the reaction can be better controlled and thus produce a better yield. It deprotonates the ammonium salt.

Reactions and processes were designed to minimize potential for accidents; waste problems were minimized as the lab manual requested we only take the amount of materials we need; regarding atom economy, most materials used were incorporated into the reaction, with the exception of leftover waste after gravity filtration and vacuum filtration

Hexane and water: immiscible; hexane on top layer Dichloromethane and water: immiscible; water on top layer Ethanol and water: miscible Ether and water: immiscible; ether on top layer

Phenol is more acidic than cyclohexanol as a result of resonance stabilization. When forming the conjugate base of phenol, electrons are delocalized throughout the ring; that is not the case for cyclohexanol.

No; the pKas are too similar

We did not measure the pure samples on different machines. However, if we did and there were differences, these may be a result of differing temperature ranges or ramp rate, or perhaps one machine heating up quicker than the other as a result.

I would expect the melting point to stay the same because in both cases, the machine must preheat to the same temperature. Furthermore, the melting point value is fixed, meaning the sample should mainly have its melting point be within a certain range.

No, it is not possible because the compound is at least somewhat soluble in the solvent it is extracted from; therefore, some of the compound will stay in the solvent and not be extracted.

chemical waste

solid waste container

stockroom window

waste can

Sponges

Drying your hands ONLY

Immediately

Look at temperature range from when the first drop of liquid is observed (starting temp) until last bit of solid has liquified (final temp)

- narrow - 1-2 degrees at most

- Lower - Broader

poor heat transfer to the sample

The sample must be finely powdered and firmly packed into a capillary tube

No!

functional groups

the structure and bonding in a molecule

pain reliever and fever reducer

carcinogenic

Amide synthesis; Williamson ether synthesis

- Completely dissolves both the desired component and any other organic impurities when hot - Desired component will not be dissolved at cold temperature

to maximize crystal formation

amine; to make it more water soluble and a better leaving group

to deprotonate the amine on p-phenetidine

No; this also leads to lower melting points

due to a small amount of impurities caused by air oxidation of the amino functional group of the compound

Extraction dissolves product, leaving impurities behind, while washing dissolves impurities, leaving the rest behind.

strictly forbidden

Department-approved

contact lenses

prohibited

tied back

protective clothing

acidic

basic

happens when tiny droplets of one liquid become suspended in the other

happens usually because of vigorous mixing; can be fixed by making the aqueous layer more polar through the addition of a small amount of brine solution followed by gently mixing or to gently swirl the liquid in the funnel

Drying organic liquids ONLY (no water droplets should be present when adding drying agent!)

not permitted

storage locker

sit

- Read labels carefully - Use spatula or scoopula when transferring solid chemicals - Never pipet any liquid by mouth - Never return excess chemicals back to bottles taken from - Clean up spills as soon as they happen - Keep lids and caps on chemical reagent bottles - When diluting concentrated acids and bases, always add acid or base to the water, not the other way around

fume hood

Never

hot

whether or not it makes a difference adding in milk or coffee first

more repetition so that there is less of a chance Tanya can get the correct answer by guessing

in actual experiment, 8 cups

random order; randomization

5% cutoff, meaning Tanya must get all 8 correct for results to be significant

Anonymous syringe

LC/MS = Liquid Chromatography/Mass Spectrometry; GC/HRMS = Gas Chromatography Coupled with High Resolution Mass Spectrometry; methods for separation of chemical compounds

C21H28O2 (THG) = 312; C20H24O3 = 312; C22H16O2 = 312

C21H28O2 (THG) = 312.20893 ; C20H24O3 = 312.172545; C22H16O2 = 312.11503

1,000 resolution; HRMS = 10,000; advantage is you can get more specific values (exact mass of compound)

THG was synthesized by hydrogenation of gestrinone

Shows S character of hydrogens and how the molecules interact with each other; different hydrogens in different positions in one molecule

Steroid has 4 carbon rings (3 6-membered rings bound together with 1 cyclopentane); cyclopentane is most important characteristic

Both steroid hormones; male has carbonyl, estradiol has OH (differing functional groups)

Anabolic means building up something; anabolic steroids help you to build up muscle