NomenclatureChemical Formulas

Reactions

Which is an example of a synthesis reaction?

A. HCl + KOH KCl + H2O

B. Pb(NO3)2 + 2HBr PbBr2 + 2HNO3

C. C + O2 CO2

D. Mg + H2SO4 MgSO4 + H2

The coefficients of the correctly balanced equation for the reaction

illustrated are —

A. 1, 1, 1

B. 1, 1, 2

C. 2, 1, 2

D. 2, 2, 1

Which of the following equations is balanced?

What would be the product(s) of this reaction?

A. 2Mg3Al2O2

B. Mg3Al2 + 3O2

C. 6Mg + Al3O2

D. 3Mg + Al2O3

Elements from which two groups in the periodic table would most likely combine with each other to form an ionic compound?

A. 1 and 2

B. 16 and 17

C. 1 and 17

D. 17 and 18

The diagram is a potential energy curve for a reaction. Which number represents the effect of a catalyst on the reaction?

A. 1

B. 2

C. 3

D. 4

Which is the correct formula for iron (III) sulfate?

A. Fe3(SO4)2

B. FeSO4

C. Fe2(SO4)3

D. Fe2(SO3)3

Remember the Roman Numeral is the charge of the Iron

*Fe’s oxidation number

Which of these represents the empirical formula and the molecular formula, respectively, for a given organic compound?

A. CH and C2H2

B. CH and CH4

C. CH2 and C2H2

D. CH3 and C3H12

 

Empirical formula is the simplest whole number ratio

Molecular formula is a multiple of the Empirical formula

The system that shows a decrease in entropy (disorder) is —

A. air escaping from a tire

B. snow melting

C. salt dissolving in water

D. water freezing

In chemical compounds, covalent bonds form when —

A. the electronegativity difference between two atoms is very large

B. electrons are completely transferred between two metals

C. pairs of electrons are shared between two nonmetal atoms

D. two nonmetal ions are attracted to each other by opposite charges

Each beaker shown above contains 2.2 grams of iron and 1 liter of 3M H2SO4 at

STP. Which reaction will go to completion first and

why?

A. Beaker A because of increased surface area

B. Beaker B because of increased surface area

C. Beaker A because of a higher concentration level

D. Beaker B because of a higher concentration level

A catalyst is a substance used in chemical reactions to —

A. provide a higher activation energy pathway

B. decrease collisions between reactant molecules

C. increase the rate of the reaction

D. change the equilibrium to favor products

Which reaction type best describes the reaction above?

A. Combination

B. Decomposition

C. Single replacement

D. Combustion

? AgNO3 + ?AlCl3 → ?AgCl + ?Al(NO3)3

A. 3, 3, 2, 1

B. 3, 1, 3, 1

C. 1, 6, 1, 9

D. 9, 3, 3, 3

Which of these sets of coefficients will balance this equation?

The formula for lithium nitride is —

A. LiN

B. Li3N

C. Li3N3

D. NLi3

This diagram of a chemical reaction shows that the reaction is —

A. endothermic

B. exothermic

C. reversible

D. at equilibrium

Ni(C2H3O2)4

How many atoms are represented in this formula?

A. 5

B. 8

C. 28

D. 29

The correct structural formula for C2H4 is

What type of reaction does this illustration represent?

A. Decomposition

B. Synthesis

C. Single-replacement

D. Double-replacement

Which of these reactions shows simple chemical decomposition?

A compound has 50% sulfur and 50% oxygen. What is its empirical formula?

A. SO4

B. S2O4

C. SO3

D. SO2

A compound has 50% sulfur and 50% oxygen. What is its empirical formula?

156.1/56.11.32

150 molS

gS

molSx

gS

256.1/13.316

150 molO

gO

molOx

gO

A compound has 50% sulfur and 50% oxygen. What is its empirical formula?

A. SO4

B. S2O4

C. SO3

D. SO2

The Lewis electron dot system represents electrons in the —

A. outer energy level

B. inner level

C. middle level

D. core level

A(s) + B(s) D(g) + heatThe reaction shown above is —

A. an endothermic reaction

B. an exothermic reaction

C. a decomposition reaction

D. a double-replacement reaction

The correct name for MgI2 is —

A. magnesium iodide

B. magnesium iodite

C. magnesium (II) iodide

D. magnesium diiodide

If the diagram were the correct representation for the Lewis structure of a molecule, then the X would be representative of the

element —A. oxygenB. fluorineC. nitrogen D. sulfur

Chlorine and bromine are in the same family in the periodic table. According to the information in the table, what would be the correct formula for sodium bromate?

A. NaBrO

B. Na2BrO

C. Na3BrO3

D. NaBrO3

Which of the groups below has the electron dot structure shown above?

A. Noble gases

B. Halogens

C. Alkali metals

D. Transition elements

When naming a transition metal that has more than one oxidation number, the numeric value of the oxidation number is indicated by a —

A. Roman numeral

B. Greek prefix

C. subscript

D. suffix

A compound is composed of 85.64% carbon and 14.36% hydrogen. The compound has a formula mass of 42.08 grams. What is the molecular formula?

A. CH2

B. C3H6

C. C2H4

D. C2H18

Which of the following is the correct molecular shape of CH4?

A. Bent

B. Linear

C. Pyramidal

D. Tetrahedral

According to the table, which of these probably has the strongest bonds?

A. Hydrogen gas

B. Iron crystals

C. Sodium chloride

D. Water

The empirical formula for ethyne (C2H2) is —

A. CH

B. C2H2

C. CH2

D. C2H

The type of reaction represented by the above equation is —

A. single-replacement

B. double-replacement

C. synthesis

D. decomposition

When this equation is correctly balanced, the coefficient of the AlCl3

will be —A. 1B. 2 C. 4D. 6

A catalyst accelerates a chemical reaction because the —

A. catalyst decreases the number of collisions in a reaction

B. activation energy of the reaction is lowered in the presence of a catalyst

C. catalyst decreases the concentration of the reactants

D. temperature of the reaction increases due to the catalyst

A compound is composed of 58.8% C, 9.8% H, and 31.4% O, and the molar mass is 102 g/mol. What is the molecular formula for this compound?

A. C2H10O 3

B. C5H5O3

C. C5H10O2

D. CH3O3

Which of these completes this reaction?

A. Oxygen

B. Hydrogen

C. Metal oxide

D. Air

A balanced chemical equation has equal numbers of atoms of each type on both sides of the equation. This illustrates the principle of —

A. conservation of energy

B. conservation of mass

C. action and reaction

D. natural selection

The type of bond found in magnesium

chloride is —

A. covalent

B. nonpolar

C. ionic

D. metallic

If the temperature of a reaction is increased, the reaction proceeds at a much quicker rate because the —

A. activation energy increases

B. energy of the products increases

C. frequency of collisions between reactants increases

D. energy of the activated complex increases

In the above reaction, a cloudiness at completion due to colloidal suspension of sulfur appears. If the reaction is carried out at various temperatures, at which temperature would it proceed at the fastest rate?

A. 20º C B. 30º C C. 40º C D. 50º C

The formula H2SO4 is representative

of which of the following?

A. A catalyst

B. A base

C. An acid

D. An organic compound

A heated liquid placed in a closed

container will vaporize until —

A. the boundary between liquid and vapor disappears

B. all the liquid molecules become vapor molecules

C. the number of liquid molecules vaporizing equals the number of vapor molecules condensing

D. the vapor pressure is greater than the atmospheric pressure

Which compound contains both ionic and covalent bonds?

A. NH4Cl

B. MgBr2

C. CH4

D. NH3

Which of the following containers of water best shows dynamic equilibrium between vapor and liquid?

To indicate the number of atoms of each element present in a molecular compound, scientists use —

A. Roman numerals

B. superscripts

C. prefixes

D. subscripts

Using the chart, which of these combinations will probably form a precipitate?

A. Ammonium chloride

B. Barium bromide

C. Calcium chromate

D. Copper (II) carbonate

The correct name for the compound CCl4 is —

A. carbon tetrachloride

B. carbon chloride

C. monocarbon chloride

D. tetracarbon monochloride

Which of these is the general formula for a double-replacement reaction?

A. A +B AB

B. AB + XY BA + YX

C. AB + XY AY + XB

D. A + B + XY AX + BY

The correct formula of an ionic compound containing Al3+ and CO3

2- is

— A. AlCO3

B. Al(CO3)3

C. Al2(CO3)3

D. Al3(CO3)2

Which of the following is the balanced chemical equation for the reaction shown above?

A. Al + H2SO4 Al2(SO4)3 + H2

B. 2Al + 3H2SO4 Al2(SO4)3 + 3H2

C. 2Al + 3H2SO4 Al2(SO4)3 + H2

D. 2Al + H2SO4 Al2(SO4)3 + H2

Aluminum +Sulfuric Acid Aluminum Sulfate + Hydrogen Gas

The figure shows a compound containing hydrogen (H) and an unknown element Z. To which group on the periodic table does

element Z belong?

A. 13

B. 14

C. 15

D. 16

The element Z forms three bonds which means it has 3 valance electrons in addition to the pair show. That gives it 5 valance electrons. Which group has 5 valance electrons.

Which of the following is the name of the molecule PCl3?

A. Phosphorus trichloride

B. Phosphorus chloride

C. Potassium trichloride

D. Potassium chloride

The appropriate model for a decomposition reaction is —

The formula for dinitrogen tetroxide is —

A. N2O4

B. N3O3

C. N2O2

D. NO

dinitrogen tetroxide

What is the correct Lewis dot structure for arsenic?

Arsenic (As) is in group 15!

Which means 5 valance electrons

Or 5 dots!

The empirical formula for a substance is CH2. If the molecular mass of the substance

is 56, the molecular formula is

A. C2H4

B. C3H6

C. C4H8 _

D. C5H10

Molar Mass

CH2 = 1(12) + 2(12) = 14

56/14 = 4

4(CH2) =

H2O(l) H2O(g)Water molecules in a sealed jar are in a state of dynamic equilibrium because water vapor molecules —

A. are condensing at the same rate that others are evaporating

B. cease to form when the air in the jar becomes saturated

C. are evaporating faster than they are condensingD. form only at high temperatures

The diagram shows the structural formula of benzene. The empirical and the molecular formulas of benzene are, respectively —

A. CH, C2H2

B. CH, C3H3

C. C3H3, C6H6

D. CH, C6H6

6 Carbon atoms and 6 Hydrogen atoms

Divide by 6 gives you ……….

When the above equation is balanced, the coefficient of the hydrochloric acid will be

A. 2

B. 3

C. 4

D. 6

Al + HCl AlCl3 + H2

Which graph represents the reaction shown above?

2NO(g) + O2(g) 2NO2(g) ΔH = - 27 kcal

ΔH = - 27 kcal Means the reaction was exothermic releasing energyTherefore the products have less energy then the reactants

Which graph represents the reaction shown above?

2NO(g) + O2(g) 2NO2(g) ΔH = - 27 kcal

Which Graph shows less energy in products than reactants? ? ? ? ? ? ? ?

Which of the following occurs when a reaction in a solution is at equilibrium and more product is added to the solution?

A. Equilibrium shifts to produce more product

B. Equilibrium shifts to produce more reactant

C. No change will occur

D. The reaction will stop

What shape does the molecule BF3 have?

A. Bent

B. Linear

C. Tetrahedral

D. Trigonal planar

Boron (B) is in group 13 therefore B has three valance electrons.

Fluorine (F) is a Halogen and therefore has 7 valance electrons

F and B Bond by 3 bonds

B

F

FF

When the above equation is balanced, the

coefficients in order are — A. 1, 1, 1, 1

B. 2, 1, 1, 2

C. 3, 1, 3, 2

D. 3, 2, 3, 1

CaSO4 + Al(OH)3 Ca(OH)2 + Al2(SO4)3

The correct name for P2O5 is —

A. phosphorus (V) pentoxide

B. phosphorus oxide

C. phosphorus (II) oxide

D. diphosphorus pentoxide

Which set of coefficients will balance this equation?

A. 1, 3, 1, 1

B. 2, 3, 2, 6

C. 2, 6, 2, 3

D. 3, 6, 3, 2

Using the table, what is the correct formula for ammonium phosphate?

A. NH4PO4

B. (NH4)2(PO4)3

C. (NH4)3PO4

D. NH4(PO4)3

Which half-reaction represents reduction?

A. Cu0 → Cu+2 + 2e-

B. Fe+2 → Fe+3 + 1e-

C. Ag+1 + 1e- → Ag0

D. Al0 → Al+3 + 3e-

Which of the following best represents the reaction between hydrochloric acid and sodium hydroxide?

A. 2HCl + 2NaOH → Na(OH)2 + H2Cl2

B. HCl2 + 2Na(OH)2 → 2H2O +2NaCl + OH

C. HCl + NaOH → H2O + NaCl

D. 2HCl + Na(OH)2 → 2H2 + NaCl + O2

The type of formula that shows the arrangements of atoms and bonds is called —

A. empirical

B. chemical

C. molecular

D. structural

What is the molecular formula of a substance that has an empirical formula of C2H5 and a molecular mass of 58 g/mole?A. C2H5

B. C5H2

C. C4H10

D. C6H15

Molar Mass C2H5 = 2(12) + 5(1) = 29g/mole

58/29 = 2

2(C2H5) = C4H10

Which type of reaction is represented here?

A. Single replacement

B. Double replacement

C. Synthesis

D. Decomposition

Na2CO3 + Ca(OH)2 2NaOH + CaCO3

The empirical formula for C6H12 is —

A. C3H6

B. C2H4

C. CH3

D. CH2

Which completes the chemical equation above?

A. O2

B. O3

C. ClO

D. ClO2

2O3 (g) 3 ______ (g)

Total of 6 O