Noun Past Questions with Answers: CHM101 – Introductory Inorganic Chemistry

Organic compounds can be obtained from __________ and
can also be made synthetically in the laboratory.
ANS=NATURAL SOURCES
2.________ organic chemistry involves the determination of
organic compounds.
ANS=QUALITATIVE
3.The most obvious method of using a balance is known as________?
ANS=DIRECT WEIGHING.
4.__________system not only measure total mass but
also may determine such characteristics as average weight
and moisture content?
ANS=ELECTRONIC WEIGHING.
5.Balances in the sortorius 2400 series allow one to determine
weight (mass) to within___________?
ANS=0.0001g
6.List the tree types of balances known to you and state the
range of their measurements??
7.The use of large flame during heating my lead to______?
8.A substance that does not burn in flame is probably a_____?
9._________are those in which a substance,usually a solid, is weighed.
ANS=GRAVIMETRIC PROCEDURES.
10.When isolation of a pure solid is difficult,or rapid filtration is necessary,_______is employed??
ANS=VACUUM FILTERATION.
11.A________is a small machine (with several test tube holder)that rotates rapidly.
ANS=centrifuge
12.Before a —— is turn on a test tube must be placed opposite the test tube of interest to prevent excessive vibration
ANS=CENTRIFUGE
13.___________is a technique employed to purify an organic solid that may be contaminated by impurities.
ANS=RECRYSTALLIZATION
14.__________of most organic compounds in common solvent increases as the temperature is increases?
ANS=SOLUBILITIES
15.dissolution are generally endothermic process.YESNO
ANS=YES
16.What are the two conditions for selecting a desired solvent for recrystallization??
ANS=a.the solubility of the desired substances in the solvent at high temperature and b.the solubility of the impurity in the solvent at lower temperature.
b.the solvent should not react chemically with the desired substance.
17.___________is a useful method for purification and isolation, but it is restricted to solids, and it is a relatively
inefficient way to separate a mixture of very similar compounds.
ANS=CRYSTALLIZATION
18.___________is the general term for the recovery of a substance from a mixture by
bringing it into contact with a solvent that preferentially dissolves the desired material.
ANS=EXTRACTION
19.The process of extraction is concerned with the_______??
ANS=DISTRIBUTION LAW OR PARTITION LAW
20.___________prevent a sharp boundary between layers?
ANS=EMULSIONS.
21.All methods of separations depends on_________?
22._______prevent a sharp boundary between two immiscible solvent layers in a separating funnel
ANS=EMULSIONS
23.Those properties that substances exhibit without undergoing a change in chemical composition are______?
ANS=PHYSICAL PROPERTIES.
24._________ are those that substances can exhibit only when undergoing a change in chemical composition?
ANS=CHEMICAL PROPERTIES
25.The temperature at which the liquid and the solid state of a substance are in equilibrum is called________?
ANS=MELTING POINT
26.during melting point determination,it is advisable to__________?
ANS=CALIBRATE THE THERMOMETER
27.The temperature at which the vapour pressure equals the applied pressure is__________?
ANS=BOILING POINT.
28.The density of a substance varies with______?
ANS=TEMPERATURE
29.Most pure substance have_________melting point?
ANS=SHARP