Final Exam
Determine the charge of an unknown ion, A, in the compound A2S.
+1
Calculate the number of moles in 38.7 g of phosphorus pentachloride.
0.186 mol
A sample of N2 gas is confined to a 14.0 L container at 375 torr and 37 degrees C. How many moles of N2 are in the container?
0.272 mol
Determine the molarity of a solution made by dissolving 11.7 g of Calcium nitrate in water where the final volume of the solution is 250.0 mL.
0.285 M
What is the molality of a solution prepared by dissolving 45.38 g of Cadmium bromide in 375.0 g of water?
0.4446 m
Automobile batteries use 3.0 M H2SO4 as an electrolyte. How much 1.20 M NaOH will be needed to neutralize 225 mL of battery acid? H2SO4(aq) + 2NaOH(aq) --> 2H2O(l) + Na2SO4(aq)
1.1 L
What is the mass (g) of one arsenic atom?
1.24 x 10^-22 g
What is the theoretical yield of vanadium in moles, that can be produced by the chemical reaction of 1.0 mole of V2O5 with 4.0 moles of calcium based on the following chemical equation? V2O5(s) + 5Ca(l) --> 2V(l) + 5CaO(s)
1.6 mol
Calculate the percent by mass of potassium nitrate in a solution made from 45.0 f potassium nitrate and 295 mL of water. Density is 0.997 g/mL.
13.3%
Determine the molar mass of Freon-11 gas if a sample weighing 0.597 g occupies 100 cm3 at 95 degrees C and 1000 mmgHg.
137 g/mol
What is the volume of a container that contains 14.3 g of a substance having a density of 0.988g/cm3?
14.5 cm3
What mass of FeS is formed if 9.42 f of Fe reacts with 68.0 g of S8?
14.8 g
How many moles are in 8.73 x 10^25 atoms of Boron?
145 moles
Determine the number of electrons and identify the correct symbol for an atom with 17 protons and 18 neutrons.
17 electrons, 35/17Cl
What is the electron configuration for Bromine?
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p5
Select the answer that expresses the result of this calculation with the correct number of significant figures 13.602 x 1.90 x 3.06 ---------------------- 4.2 x 1.4097
2 sig figs --> 13
1.75 moles of H2O2 were placed in a 2.5 L reaction chamber at 307 degrees C. After equilibrium was reached, 1.20 moles of H2O2 remained. What is K for the reaction?
2.3 x 10^-2
For the nitrogen fixation reaction, 32(g) + N2(g) <--> 2NH3(g), K = 6.0 x 10^-2 at 500 degrees C. If 0.250 M H2 and 0.050 M NH3 are present at equilibrium, what is the equilibrium concentration of N2?
2.7 M
A sample of gas occupies 1.40 L at 25 degrees C and 760 mmHg. What volume will it occupy at the same temperature and 380 mmHg?
2.8 L
What is the coefficient for O2 in the balanced equation? _____ C7H14 + _____ O2 --> _____ CO2 + _____ H2O
21 O2
How many mL of 0.0150 M KOH are required to react exactly with 75.0 mL of 0.0150 M H3PO4?
225 mL
True/False The rusting of a piece of iron under environmental conditions is a physical change.
False
Which of these chemical equations describes a single replacement reaction?
Fe2O3(s) + 2Al(s) --> 2Fe(s) +Al2O3 (s)
Which of the following is a metalloid?
Germanium
Which of the following pure substances will exhibit hydrogen bonding?
H2O (FON home)
Which of the following equations is a redox reaction?
H2O(l) 9 NH3(g) --> NH4(aq) +OH-(aq)
Which of the following is a strong acid?
H2SO4
What is the conjugate base of water?
H3O+
What is the conjugate acid of CO3^2 in the reaction below?
HCO3-
Which substance has the lowest vapor pressure at room temp?
HF
The elements in group 7A are known by what name?
Halogens
Identify the net ionic equation for the following reaction. 2NaCl(aq) + Hg2(NO3)2(aq) --> 2NaNO3(aq) + Hg2Cl2(s)
Hg2^2(aq) + 2Cl-(aq) --> Hg2Cl2(S)
What is the chemical formula for diionide pentaoxide?
I2O5
Place the following in order of increasing electronegativity.
K < Se < Cl
For the exothermic reaction below, if heat is added to the system, what will happen to the equilibrium H2(g) + Cl2(g) <--> 2HCl(g)
equilibrium will shift LEFT
For the endothermic reaction below, if heat is removed from the system, what will happen to the concentration of carbon monoxide? CH4(g) + H2O(g) <--> CO(g) + 3H2(g)
it decreases
What is the molecular geometry of the thiocyanate anion (SCN-), as predicted by the VSEPR model?(Carbon is the central atom)
linear
Predict the molecular geometry and polarity of the CS2 molecule.
linear, nonpolar
What is the name of P4Se3?
tetraphosphorus triselenide
According to the VSEPR model, the predicted molecular geometry of ammonia, NH3, is:
trigonal pyramidal
True/False The mass of a neutron is equal to the mass of an electron.
False
Determine which sublevel designation is not legitimate
2d
The number of resonance structures for the nitrate ion that satisfy the octet rule is:
3
The Lewis structure for a chlorate ion, ClO3- should show _____ single bond(s), _____ double bond(s), and _____ lone pair(s).
3, 0, 10
What is the molarity of a solution prepared by diluting 1.85 L of 6.5 M KOH to 11.0 L?
3.1 M
Compounds A, B, and C react according to the following equation. 3A(g) + 2B(g) --> 2C(g) [A] = 0.855 M [B] = 1.23 M [C] = 1.75 M
3.24
What volume of chlorine gas at 25 degrees C and 0.950 atm can be produced by the reaction of 12.0 g of MnO2 in excess HCl (aq)? MnO2(s) + 4HCl(aq) --> MnCl2(aq) + 2H2O(l) + Cl2(g)
3.55 L
What is the mass, in grams, of 2.74 L of CO gas measured at 33 degrees C and 945 mmHg?
3.80 g
A sample of nitrogen gas at 298 K and 745 torr has a volume of 37.42 L. What volume will it occupy if the pressure is increased to 894 torr at a constant temp?
31.2 L
A sample of N2 gas occupies 2.40 L at 20 degrees C. At what temp will the N2 gas occupy a volume of 4.80 L at constant pressure?
313 degrees C
The number 1.050 x 10^9 has how many sig figs?
4
What is [OH-] for a solution at 25 degrees C that has [H3O+] = 2.35 x 10^-3 M?
4.26 x 10^-12 M
How many atoms are in 7.12 mol of gold, Au?
4.29 x 10^24 atoms
Calculate the mass in grams of 3.65 x 10^20 molecules of sulfur trioxide (SO3).
4.85 x 10^-2 g
What volume of a 0.442 M NaOH solution is needed to neutralize 65 mL of a 0.296 M solution of HNO3?
43.5 mL
A sample of nitrogen gas has a volume of 32.4 L at 20 degrees C. The gas is heated to 220 degrees C at a constant pressure. What is the final volume of the nitrogen gas?
54.5 L
If 119.3 g of PCl5 are formed from the reaction of 61.3 g Cl2 with excess PCl3, what is the percent yield? PCl3(g) + Cl2(g) --> PCl5(g)
66.3%
What is the mass of 1.63 x10^21 atoms of silicon?
7.61 x 10^-2 g
Determine the number of protons, electrons, and neutrons for the isotope gold-118. The symbol for gold is Au.
79 pro, 79 elec, 39 neu
Determine the mass of H (in grams) that contains 5.08 x 10^15 H atoms.
8.51 x 10^-9 g
What is the volume (in mL) of a 32.0 fl oz can of juice? (1 fl oz = 29.6 mL)
947 mL
Based on the solubility rules, which of these compounds is soluble in water?
AgNO3
Which element would be expected to have properties similar to calcium?
Ba
Which of these compounds is most likely to be ionic?
BaCl2
Place the substances in order of INCREASING boiling point.
BeF2 < BF3 < NF3
Select the pair of substances in which the one with the HIGHER vapor pressure at a given temperature is listed first.
CCl4, CBr4
Which has the highest surface tension at room temp?
CI4
What is the formula for the ionic compound formed by calcium ions and nitrate ions?
Ca(NO3)2
Place the substances in order of DECREASING boiling point.
Cbr4 > BeBr2 > BeCl2
Which pair of elements would be most likely to form an ionic compound?
F and Al
True/False Ethanol (C2H5-OH) will have a greater viscosity than ethylene glycol (HO-CH2CH2-OH) at the same temperature.
False
If 31.3 f of manganese (II) chloride, 48.3 f of chlorine gas, and 25.7 g of water react to produce manganese (IV) oxide and hydrochloric acid, what is the limiting reactant? What mass of hydrochloric acid is produced?
Manganese (II) chloride is the limiting reactant and 36.3 g of hydrochloric acid is produced
What is the name of Mn(CO3)2?
Manganese (IV) Carbonate
Based on the solubility rules, which one of these compounds is soluble in water?
Na2S
The formula for sodium sulfide is:
Na2S
Select the compound in which sulfur has its highest possible oxidation number.
Na2SO4
Which of the following elements exist as a diatomic molecule?
O (BrINClHOF)
What is the formula for lead (II) oxide?
PbO
If aqueous solution of lead (II) nitrate and sodium sulfate, which insoluble precipitate would form?
PbSO4
Which of the following are most likely to be covalent?
SF4
Which element has the following ground-state electron configuration? [Kr]5s2 4d10 5p3
Sb
Which ground-state atom has an electron configuration described by the following orbital diagram? [Ar] 4s2 3d10 4p4
Selenium
For the reaction below, if Chlorine gas is added to the system, what will happen to the equilibrium? 2NOCl(g) <--> 2NO(g) + Cl2(g)
The equilibrium will shift LEFT
Which of the following statements is true?
The stronger the intermolecular forces, the higher the viscosity.
True/False Zero Kelvin 0K < 0F < 0C
True
The elements in a column of the periodic table are known as
a group
Consider the element with the electron configuration [Kr] 5s2 4d7. The element is:
a transition metal
Two isotopes of an element differ only in their:
atomic mass
Predict the molecular geometry and polarity of the SO2 molecule.
bent, polar