Chemistry Final EXAM 2
Nonmetals tend to _____ electrons to form ions of _____ charge. gain, negative lose, positive lose, negative gain, positive
Gain, negative
For the reaction: 4NH + 5O → 6H O + 4NO If 2.5 moles of NH is reacted with 3.0 moles of O2 , what is the limiting reagent?
02
Calculate the number of moles in a 233 gram sample of barium. 1.70 moles 6.022 × 10 moles 23 1.02 × 10 moles 24 3.20 × 104 0.589 moles
1.70 Moles
Determine the mass in grams of 3.45 × 10 molecules of oxygen, molecules of O2. 0.556 grams 458 grams 57.2 grams 916 grams 1.83 × 10 grams 3
1.83x10^3 grams
Determine the mass of one mole of silver. 107.87 amu 47 amu 6.022 × 10 amu 23 47 g 107.87 g
107.87 g
How many grams of nitrogen dioxide are required to produce 260 grams of nitrogen monoxide? 3NO2 + H2O → 2HNO3 + NO 56.52 grams 132 grams 8.67 grams 1196 grams 399 grams
1196 grams
Which of these is not equivalent to one mole? 28 grams of nitrogen, N2 12 grams of magnesium 6.022 × 10 marbles 23 Avogadro's number 12 grams of carbon
12 grams of magnesium
Determine the correct number of protons and electrons in P . 3− 15 protons, 12 electrons 31 protons, 34 electrons 15 protons, 18 electrons 31 protons, 28 electrons 3 protons, 6 electrons
15 Protons, 18 electrons
For the reaction: 4NH + 5O → 6H O + 4NO If 125.0 g of NH is reacted with 225.0 g of O , how many grams of NO will be present after a complete reaction? 0 grams 220.6 grams 350.0 grams 168.8 grams
168.8 grams
How many moles of oxygen gas will react with 6.2 moles of aluminum? 4Al(s) + 3O (g) → 2Al O (s) 2 2 3 4.65 moles 1.55 moles 2.4 moles 0.12 moles 8.27 moles
4.65
What is the coefficient in front of HF when the equation is balanced? ______ B2O3 + __ HF → __ BF3 + __ H2O
6
What is the correct number of atoms in one mole of aluminum? 13 6.022 × 1023 26.98 12 14
6.022 × 1023
Calculate the number of oxygen atoms in 45.0 g of Co (SO ) (molar mass =405.8 g/mole). 6.68 × 10 atoms 22 1.07 × 10 atoms 24 8.01 × 10 atoms 23 2.67 × 10 atoms 23 12.0 atoms
8.01 X 10^23
Radon −222 has _____ protons, _____ neutrons, and _____ electrons. 86, 222, 86 86, 136, 222 86, 86, 86 86, 222, 308 86, 136, 86
86, 136, 86
A certain ion contains 47 protons and 46 electrons. The ion is: Can't tell from the given information Pd+ Ag+ Pd− Ag−
Ag+
Which of these is the correct formula for aluminum oxide? AlO2 Al2O2 Al2O3 AlO Al3O2
Al2O3
Strontium is a member of what group/family? noble gases alkaline earth metals transition metals halogens alkali metals
Alakline earth metals
Which of these statements about Bohr's model of the atom is correct? The greater the quantum number the higher the energy of an orbit. Elements with the same number of electrons in their outer orbit have similar properties. All of these statements are correct. Electrons occupy orbits with certain radii corresponding to discrete energies. Electrons fill lower energy orbits first.
All of these statements are correct.
Which of these statements best describes the formation of an anion? An atom gains one or more electrons and becomes negatively charged. An atom gains one or more electrons and becomes positively charged. An atom loses one or more electrons and becomes negatively charged. An atom loses one or more electrons and becomes positively charged.
An atom gains one or more electrons and becomes negatively charged.
The elements of group 7A will all form ions. These ions will be _____ and will have a charge of _____. cations, 2+ anions, 2− anions, 1− cations, 3+ cations, 1+
Anions, 1
Which of these statements concerning atomic mass is correct? Atomic mass is a weighted average of the masses of the naturally occurring isotopes. Atomic mass is the same as the mass number of the most common isotope. Atomic mass is derived from the weight of the most common isotope of the element. Atomic mass is determined by adding the masses of the protons, electrons, and neutrons in the atom. Atomic mass is calculated from the atomic mass of the two most common isotopes.
Atomic mass is a weighted average of the masses of the naturally occurring isotopes
Which of these statements about atoms is incorrect? Atoms are composed of protons, neutrons, and electrons. There are 91 different naturally occurring atoms. Atoms are the smallest visible amount of an element. Atoms are the smallest identifiable unit of an element. Atoms are the building blocks of all matter.
Atoms are the smallest visible amount of an element
Barium fluoride is often used in glass manufacturing. Which of these is the correct formula and bonding type for barium fluoride? BaF2, ionic BaF, ionic BaF, covalent BaF , covalent 2 Ba2F, ionic
Baf2, ionic
Which of the following elements is generally not found in diatomic form in nature? C N F O
C
Which of these is the correct chemical formula for carbon tetrachloride? CCl4 C Cl 4 None of the listed CCl5 CCl3
CCl4
Which of these is not a covalent compound? CH4 ICl3 SiO2 N2O CaO
CaO
Which of these is the correct name for Ca(OH)2? Calcium hydroxide Calcium dihydride Calcium oxygen hydride Calcium oxide Calcium carbonate
Calcium Hydroxide
When a strontium atom loses two electrons, it becomes a(n) _____ with a charge of _____. anion, 2− cation, 0 cation, 2+ cation, 2− anion, 2+
Cation, 2+
Which of these elements has seven valence electrons? Cl S Al Mg Li
Cl
He has the same number of valence electrons as _____. F Be Ne H
H
Which statement about ionic compounds is incorrect? Ionic compounds are held together by attraction between positive and negative ions. Ionic bonds are formed between metals and nonmetals. Ionic solids dissolved in water will conduct electricity. Ionic bonds involve the sharing of electrons by metals and nonmetals. Ionic compounds include table salt, calcium carbonate, and sodium bicarbonate.
Ionic bonds involve the sharing of electrons by metals and nonmetals
Methane can be decomposed into two simpler substances, hydrogen and carbon. Therefore, methane must have the formula CH. is a gas. is a compound. is an element. is a mixture.
Is a compound
Which of the following is not true for 3 moles of CaCO3? It contains 3 moles of O. None of the listed. It contains 3 moles of Ca. It contains 9 moles of O. It contains 3 moles of C.
It contains 3 moles of O
Which element is not a nonmetal? Cl K I N P
K
Which of these is the correct chemical symbol for potassium? K P Pt Po Pd
K
Which of these is the correct formula for potassium phosphate? K (PO ) 2 4 3 KPO4 K3PO4 K3P K(PO )4 3
K3PO4
Which of these is the correct name for Li2SO4? Lithium sulfate Lithium sulfide Dilithium sulfate Dilithium sulfide Dilithium tetrasulfide
Lithium Sulfate
A tiny amount of magnesium chloride contains 150 magnesium ions and 300 chloride ions. The correct formula for magnesium chloride is: Mg2 Cl MgCl MgCl2 Mg Cl 150 300
MgCl2
Which of these substances is a compound? Pb NO Na Cl2 H2
NO
The correct formula for the nitrate ion is: none of the listed NO3 − NO3 2− NO3− NO−
NO3-
Which of these elements is not a transition metal? Fe Na Ag Cu Hg
Na
There are three isotopes of neon. Assuming the mass of each isotope is very close to its mass number, which isotope is most abundant based on the atomic mass of neon (Ne)? Ne-20 Ne-22 Can't tell from the given information. Ne-21
Ne-20
Elements in the same group have the same _____. number of valence electrons mass number number of protons number of electrons atomic number
Number of valence electrons
Which of these will not form a positive ion in an ionic compound? Rb Sn Mg Ba P
P
What is the correct name of K2O? Potassium monoxide Potassium oxide Potassium oxygen Dipotassium oxide Dipotassium monoxide
Potassium oxide
Isotopes of an element have the same number of _____ but a different number of _____. electrons, protons neutrons, protons neutrons, electrons protons, electrons protons, neutrons
Protons, Nuetrons
Which of the following is not true for an atom that has an atomic number of 19 and a mass number of 41? The atom contains 19 neutrons. The atom contains 19 electrons. The atom is potassium. The atom contains 22 neutrons. The atom contains 19 protons.
The atom contains 19 neutrons.
Which of these statements about an atom is incorrect? The number protons equals the number of electrons. The mass number is the sum of protons and neutrons in the atom. The mass number minus the atomic number equals the number of neutrons in the atom. The number of protons equals the number of neutrons. The number of protons equals the atomic number
The number of protons equals the number of nuetrons
What are the Z and A values for an atom of silicon which contains 15 neutrons? Z=15, A=29 Z=15, A=14 Z=29, A=14 Z=14, A=29 Z=14, A=15
Z=14, A=29
Mendeleev organized the elements of the periodic table by increasing atomic weight and similar properties. alphabetically. by increasing number of electrons. by increasing atomic number and similar properties. by increasing number of isotopes.
by increasing atomic weight and similar properties
