Chemistry for Everyone: Exam 2
The oxidation number of a pure sample of a group 2 element
0
What are the oxidation numbers for the metals in the equation below for a zinc/silver battery? 2 Ag(s) + ZnSO4(s) --> Zn(s) + Ag2SO4
0, 2+, 0, 1+ respectively
The density of N2 at STP is...
1.25 g/L
How many individual molecules of AlCl3 are contained in 0.450 mols of AlCl3?
2.71 X 10^23 molecules
A sample of radon gas is contained in a 5.00 L vessel at a temperature of 28.1 degrees C and a pressure of 14.9 atm. Calculate the number of mols inside the vessel. (R = 0.0821 Lxatm/molxK)
3.01 mol (use PV=nRT)
The boiling point of chlorobenzene is 131.70 degrees C. What is this temperature on the Kelvin scale?
404.85 K
Select the answer with the correct number of significant figures for the following: 0.326 - 19.56789 + 487.3 =
468.1
A sample of gas in a balloon has an initial volume of 18.5 L at 18 degrees C. If the temperature of the balloon is decreased to -194 degrees C, what is the final volume of the balloon?
5.0 L (use V1/T1 = V2/T2)
What is a Bronsted-Lowry base?
A proton acceptor
What is a Bronsted-Lowry acid?
A proton donor
Ammonia (NH3) boils at -33 degrees C, water boils at 100 degrees C and ethanol (CH3CH2OH) boils at 78 degrees C. What is the rank of intermolecular forces in these liquids from weakest to strongest?
Ammonia < Ethanol < Water
Swamps and other stagnate bodies of water often have a bad smell to them, this is due to the breakdown of organic matter by what pathway?
Anaerobic
A substance that produces H+ in aqueous solutions
Arrhenius acid
A substance that produces OH- in aqueous solutions
Arrhenius base
Considering intermolecular forces, which compound would have a higher boiling point, CH3CH2OH or CH3CH2CH3?
CH3CH2OH
In the neutralization reaction of Ca(OH)2 and HNO3, the products are water and...
Ca(NO3)2
Hard water would most likely contain relatively large concentrations of...
Ca2+ ions
The term for when a gas becomes a liquid
Condensation
As the pressure of an ideal gas increase, the volume will do what?
Decrease
The ozone hole over Antarctica has ___________ since 2006.
Decreased
Pentane has the formula CH3CH2CH2CH2CH3. What is the predominant intermolecular force between pentane molecules? (EN of C = 2.5, EN of H = 2.1)
Dispersion forces
Propane has the formula CH3CH2CH3. What is the predominate intermolecular force between propane molecules? (EN of C = 2.5, EN of H = 2.1)
Dispersion forces
Strong acids and bases do what in aqueous solutions?
Dissociate completely into ions
In the reaction (Cu+) + Fe --> Cu + Fe2+ (Note: the reaction is not balanced)
Fe is oxidized, Cu+ is reduced, and Cu+ is an oxidizing agent
Has no definite volume and no definite shape
Gas
According to the kinetic-molecular theory, gas molecules...
Have weak interactions between molecules, are in constant, rapid, linear motion, and collide and transfer energy to each other perfectly.
As the temperature of an ideal gas increases, the volume will
Increase
What best classifies the attraction between an ion and water molecules?
Ion-dipole interactions
In the neutralization reaction of NaOH by H2SO4, the products are water and...
Na2(SO4)
The most abundant gas in our atmosphere
Nitrogen
The second most abundant component of atmospheric air is...
Oxygen
Radon gas is ____________
Radioactive
A buffer...
Resists changes in pH when small amounts of a strong acid or a strong base is added
When an acid and base come into contact with each other the resultant reaction is called a neutralization reaction. What are the products of such a reaction?
Salts and water
A solution with [H3O]+ = 2.0 X 10^-9 M is...
Slightly basic (pH = log [H+])
The term for when a solid becomes a gas
Sublimation point
Solid water has a lower density than when it is in its liquid form. In other word, ice floats on water! This unique property is best attributed to...
The large empty spaces in the hydrogen bonding network of H2O (solid)
Which layer of the earth's atmosphere contains nearly all living things?
Troposphere
Which of the following compounds will NOT dissolve in water? a. CH3CH2CH2CH2CH3 b. CaCl2 c. CH3OH d. Na2SO4
a.
Which of the following oxides (also called anhydrides) will give a basic solution in water? a. K2O b. CO c. SeO2 d. P2O5
a.
Which of the following statements about ozone (O3) is correct? a. Ozone is important to life on earth b. Ozone is always a pollutant c. It is good for your health to breathe in ozone d. Ozone is not a pollutant anywhere in the atmosphere
a.
In a redox reaction, oxidation occurs at the...
anode
In which of the following unbalanced half-reactions is the reactant undergoing reduction? a. H2 --> H2O b. SiO2 --> SiF2 c. Zn --> Zn2+ d. C3H9 --> C3H7
b.
The temperature at which a liquid becomes a gas is called the...
boiling point
All of the following are acids EXCEPT? a. HCl b. HNO3 c. Mg(OH)2 d. H3PO4
c.
For which of the following is hydrogen bonding NOT a factor? a. H2O b. NH3 c. CH4 d. CH3OH
c.
Which of the following is NOT a definition of reduction? a. Reduction is the loss of oxygen from a substance b. Reduction is the addition of hydrogen to a substance c. Reduction is the loss of electrons from a substance d. Reduction is the gain of electrons by a substance
c.
Which of the following pure compounds would be capable of hydrogen bonding? a. NaCl b. PHCl2 c. NH3 d. C7H16
c.
Which of the following is the strongest intermolecular force? a. Dipole-dipole forces b. Dispersion forces c. Hydrogen bonds d. Ion-dipole forces
d.
Earth's oceans cover approximately 75% of the planet's surface. These large bodies of water serve to moderate Earth's temperature due to what unique property of water...
high specific heat