Chem Final Exams 1 & 2
The unit of weight used for precious stones is the carat (1 carat=200mg, exactly ;). If a particular 1.25 carat diamond cost $1000, what is the cost of a collection of identical diamonds which weighs .3086 ounce?
$35000
What is the formula of the compound formed between the ammonium ion and the carbonate ion?
(NH4)2CO3
The boiling point of liquid nitrogen is 77k what is this temperature on the centigrade scale
-196c
Which of the following is the isopropyl group
-CHCH3
Saline solutions used to deliver intravenous drugs are .89%. What mass of NaCl is fond in 50. ML of such a solution
.45 g
How many liters are there in 1 microliter
1 x 10-6
In an aqueous solution the [H+] is 1.0 x 10-5M. What is the [OH-]
1.0 X 10-9 M
Aluminum has a density of 2.7 g/cm3. What volume is occupied by a block of aluminum which weighs 4.32 kg?
1.60L
What bond angle is most closely associated with a tetrahedral distribution of electron density?
109.5
At a constant temperature the pressure on an 6 liter sample of gas is reduced from 2 ATM to 1 ATM what is the new volume of the gas sample
12 liters
A closed flask contains a .25 moles of O2 which exerts a pressure of .50 ATM. If 0.75 moles of CO2 is added to the container what is the total pressure in the flask
2.0 ATM
How many hydrogen atoms are in a molecule of acetic acid HC2H3O2
2.408x10^24
A particular model of hybrid car can travel 35 miles/gallon of gas. What is this fuel efficiency expressed in the metric system?
22.5 km/liter
The boiling point of ocean is 126c what is this temperature on the Fahrenheit scale
259f
Nitrogen dioxide, NO2, is a brown gas found in smog. It can produced by the reaction of nitric oxide, NO, with molecular oxygen in the air which of the following is the correctly balanced chemical equation for the reaction?
2NO(g)+O2(g)->2NO2(g)
AT constant pressure the temperature of a 4 liter sample of gas is decreased from 400 k to 300 k. What is the new volume of the gas sample
3 liters
What is the IUPAC name of
3,4-dimethylhexane
Suppose a balloon is filled so that its volume is 2 L when the pressure is 1.10 ATM and the temperature is 300k. What volume will occupy if it rises to an elevation where the pressure is 338 mm Hg and the temperature is 200 k?
3.30 L
How much does one mole of oxygen gas weight?
32 g
A common piece of laboratory glassware is a 125 ml beaker. What is this volume in the English system of units?
4.23 fl oz
Which of the following columns of the periodic table is not commonly identified by a name
4A
Consider the following heating curve for the generic substance Z. (Insert BS graph here) What is the temperature range for liquid substance Z
50c
How many electrons are associated with a triple bond?
6
Which of the following pH's corresponds to a slightly acidic solution
6.8
A slot water solution is 3%. How much salt is there in a sample which weights 250 grams
7.5 grams
For the reaction 2KClO3(s)->2KCl(s)+3O2(g), how much oxygen is produced when 5.00 moles of starting material is completely decomposed?
7.5 moles
A particular chemical reaction carried outa at 40c takes 2 hours. How long will it take to carry out the reaction at 20c
8 hours
A solution has a pOH of 5.4. What is it s pH
8.6
The active ingredient in the household bleach is sodium hypochlorite, NaClO2-. What is the formula weight of sodium hypochlorite?
90.5 amu
When a particular solid sample is examined under a microscope it is observed that there are regions which are black and region which are yellow. What type of material is this sample?
A heterogeneous mixture
Which of the following statements is true of a mixture?
A mixture does not obey the law of definite composition
For the exotheermic reaction 3H2+N2-><-2NH3 which of the following changes could be carried out in such a way as to not cause the reaction to shift other to the left or to the right
Adding H2 and raising the temperature
When considering the effect of a catalyst on a system to which LeChateliers principle can be applied which of the following is true
Addition of a catalyst speeds up both the forward and reverse reaction by the same amount
What is the formula of thee compound formed by aluminum and chlorine
AlCl3
Which of the following statements all of which were part of daltons atomic theory was later shown to be false
All matter is made up of very tiny indivisible particles called atoms
Petroleum provides the raw material for which of the following
All of these
Which of the following is important sources of organic compound
All of these
Reduction can be defined as which of the following?
All of these correct defines reduction
A student is preparing a sugar water solution to make rock candy. When the student continues to add sugar to thee solution the sugar dissolves. Which kind of solution does the student have?
An unsaturated solution
Which of the following statements is false
As acid strengths decrease conjugate has strengths increase
At what temperature do thee temperature on the Celsius and Kelvin scales have the same numerical value?
At no value
For the exothermic reaction 3H2+N2-><-2NH3 which of the following changes could be carried out in such a way as to not cause the reaction to shift either to the left or to the right
Both A and B
Which of the following can be characterized as a strong electrolyte
Both A and B
Which of the following ions has the same electronic configuration as neon?
Both A and B
Which of the rolling is constitutional isomer of pentane CH3(CH2)3CH3?
Both A and B
Which of thee following is a form of potential energy
Both A and B
For the reaction A+B->2C which of the following statements is true
Both A and B are true
In a redox reaction which of the following is true for the reducing agent?
Both A and B are true
In an energy diagram for an exothermic chemical reaction which of the following is true
Both A and B are true
The combined gas law combines which gas laws
Boyles, Charles, and gay-lussacs
What is the molecular formula for the following compound? (Stick man figure with no head)
C7H16
Which of thee following is not a proper symbol for an element
CO
For which of the following pairs are the atoms most likely to form an ionic bond with each other?
Calcium and chlorine
CaO commonly called lime was once heated. In theaters to give a bright light hence the term limelight. What is the correct name for CaO?
Calcium oxide
Which of the following is not an example of an intermolecular attraction
Covalent bonding
Which of the following is associated with cells in a hypertonic solution
Crenation
Which of the following statements is generally true about electronegativity?
Electronegativy increases as we move left to right and decreases as we move top to bottom
Which of the following is the balanced molecular equation for the reaction of sulfuric acid, H2SO4, with sodium hydroxide, NaOH?
H2SO4(aq)+2NaOH(aq)->NaSO4(aq)+2H2O(l)
Which of the following is the net ionic equation for the reaction of the strong acid HCl which the strong base NaOH
H3O+(aq)+OH-(aq)->2H2O(l)
Which of the following molecules can engage in hydrogen bonding
HF
Which of the following buffer systems is important in human blood
HPO42-/H2PO4-
Alkanes are members of which class of organic compounds
Hydrocarbons
Cobalt-60 is a radioactive isotope sometimes used int eh treatment of cancer. Which of the following statements is true about an atom of cobalt-60
It contains 27 protons
Which of the following is true of a 1 gram sample of iron
It contains a very very huge number of atoms each of which has an extremely tiny mas
Which is most likely tried for an atom with six valence electrnons?
It will gain two electrons
A compound used to rest manic depressive has the formula Li2CO3. Which of the following is the correct name for this compound?
Lithium carbonate
What are the elements in the A columns of the period table called
Main group elements
Which of the following is a physical change?
Melting of ice
Which of the following is the definition of molarity
Moles of solute/liter of solution
Which of the following as an example of a combustion reaction?
N2+2O2(g)->@NO2(g)
Which of thee following is the correct formula for dinitrogen pentoxide?
N2O5
When an acid reacts with a base the reaction is called which of the following
Neutralization
The balanced equation for the complete combustion of propane is C3H8(g)=5O2(g)->4H2O(g)+3CO2(g) if 1 mole of propane and 10 moles of oxygen are placed in container, what will be left in the container after the reaction is complete?
No propane, 5 moles of oxygen, 4 moles of water vapor, 3 moles of CO2
Which of the following cannot serve as a solvent in a solution
None all can serve as solvents
According to the kinetic molecular theory, which of the following is not true
None of the above are true
Which of the following is not a base?
None, they are all bases
According to Arrhenius, what species is associated with all bases
OH-
Thee "ide" ending is usually but not always associated with monatomic anions. Which of the following polyatomic ions has a name which ends in "ide"?
OH-
Which of the following correctly describes an electron?
On the scale of subatomic particles it is light: it has a -1 charge
Which regions of a heating curve correspond to regions where only a single phase of a material is present
Regions with positive slopw
Which of the following is associated with the deesalinization of water
Reverse osmosis
What is the name of the species formed when a sodium atom loses an electron?
Sodium ion
Which of the following occurs when the weak base ammonia NH3 is dissolved in water
Some ammonia molecules take an H+ from the water
Which geometrical shape is associated with the carbon atoms in alkanes
Tetrahedral
The number of valence electrons of a main group element is related to which of the following
The elements column number
When a piece of solid magnesium is added to a hydrochloride acid the total ionic for the reaction is Mg(s)+2H+(aq)+2cl-(aq)->Mg2=(aq)+2Cl-(aq)+H2(g)
The hydrogen ion is reduced
Which of the following is characteristic of a buffer
The pH will go up very slightly when OH- is added to the buffer
Consider a sample of water in a closed container. Which of the following would indicate that the reaction H2O-><-H2O has reached equilibrium
The pressure it he container remains constant
Which of the following is true of a reaction which has reached equilibrium
The rate of the forward reaction is equal to the rate of the reverse reaction
For the endothermic reaction N2)4-><- 2NO2 what is the effect of doubling the volume of the reaction vessel
The reaction will shift left to right
For the endothermic reaction N2O4-><-2NO2 what is the effect of removing NO2 from the reaction vessel
The reaction will shift left to right
A sample of carbon dioxide occupies 22.4 liters at STP. Which of the following statements is true
The sample contains 6.02x10^23 molecules
Which of the following is the most characteristic feature of the electronic configurations of the elements in a vertical column?
Thee valence electrons are of the same type and number
A student has three gas sample. All the gases are the same temperature and pressure. If the three gases are O2,CO2,NH3, which sample contains the largest number of molecules
They all contain the same number of molecules
Which of the following is true of ice, water and steam?
They are the same substance in different physical states
When comparing one mole of water with one mole of ammonia which of thee following is true?
They contain thee same number of molecules
Which of the following is a chemical property of water?
Water reacts violently with sodium
Which of the following is true
When an organic compound is synthesized int he laboratory it is identical to the natural form of the compound
What is the correct name for XeF4?
Xenon tetrafluoride