Upgrade to remove ads
OChem Lab Test 1
Terms in this set (32)
Known to cause cancer
Irritant to eyes
Can cause burns to skin or destroy equipment
Liable to ignite spontaneously on exposure to air
Dangerous if ingested via swallowing, inhalation, etc.
What three types of personal protective equipment could you use to reduce your exposure to hazardous chemicals in the lab?
Gloves, proper safety glasses, lab coat
List three ways the fume hoods lower the risks when working in the lab
Filter vapors from chemicals and properly remove them from the building, keeps spills contained, protects against chemical splatters or coming into contact with shattered glass if something explodes
What intermolecular forces are responsible for the solubility of polar compounds (such as sugar) in polar solvents (such as water)? Explain in full sentences.
Dipole-dipole interactions contribute to the solubility of polar compounds, but above all, the solubility to hydrogen bond allows for polar molecules to be highly soluble together
Waste: Needles and syringes
20 mL of 1:1 mixture of chloroform and hexane
Dry magnesium sulfate
10% solution of aqueous HCl
Neutralize and dispose of down the drain with water
A mixture of 10 mL ether and 10 mL toluene
Rank the following solvents in order of decreasing polarity
Water, acetone, chloroform, toluene, hexane
What two properties/characteristics of activated carbon make it very useful for removing colored impurities from solution during recrystallization?
It has a high surface area, and it would not react with the solution; It has high porosity
A student has dissolved 150 mg of a compound in 4 mL of ether, and the solution must be decolorized to remove some colored impurity. Should this solution be decolorized with Norit pellets or with powderized carbon? Explain.
The solution should be decolorized with Norit pellets because it is only 4mL of solution. For solutions of 5mL or less, one should use pellets. For anything greater then 5mL, one should use powderized carbon. Also, powderized carbon can cause clumping with the solution causing a decrease in recovery.
Which curve represents the solubility curve for a good solvent?
The slope with the 1/1 positive slope
What are the problems with the other two curves? Explain the behavior of each curve
The straight slope at low solubility is not soluble at low or high temperatures. The solute will never fully dissolve in solution, and many impurities will remain in the lattice. The straight slope at higher solubility is highly soluble at both low and high temperatures. Once it dissolves into solution, it would be very difficult to get out of solution and recrystallize
List two ways in which the presence of impurities affects the melting point/melting range of a pure organic compound
It lowers the melting point, it broadens the melting range
Some low melting solids have a tendency to "oil out" instead of dissolving when attempts are made to purify the compound by recrystallization. What simple change could you make to a recrystallization procedure if your compound "oiled out?"
If the compound "oils out," use a solvent with an even lower boiling point to prevent the mixture from ever reaching the point of melting the solute
Gives off vapors that can ignite
Known to explode under certain conditions
Causes damage to chromosomes
will oxidize an oxidizable substance (substance that can burn), may set it on fire
forms peroxides on standing or when in contact with air
Very serious and sometimes irreversible effects on the body
May cause an allergic reaction on second or later exposure
Causes birth defects and can affect fetal development
Dry calcium chloride (waste)
A mixture of 5mL ethanol and 10mL dichloromethane
10mL of 1:1 mixture of ether and hexane
5% solution of aqueous H2SO4
Neutralized, down the drain with water
Other sets by this creator
BIOL 410 - Section 2
Genetics Quiz 9&10
Genetics Test 1
Other Quizlet sets
CHEM 215 Day 8 Quiz
Fluids Test Review
Exam 2 Chp 27
Sonography and High-Risk Pregnancy