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Nomenclature Chemical Formulas Reactions. Which is an example of a synthesis reaction?. A. HCl + KOH KCl + H 2 O B. Pb(NO 3 ) 2 + 2HBr PbBr 2 + 2HNO 3 C. C + O 2 CO 2 D. Mg + H 2 SO 4 MgSO 4 + H 2. A + B AB.
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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 A + B AB
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 2 2
What would be the product(s) of this reaction? A. 2Mg3Al2O2 B. Mg3Al2 + 3O2 C. 6Mg + Al3O2 D. 3Mg + Al2O3 3 3MgO + 2Al Mg + 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 Fe3+ SO42-
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 — • air escaping from a tire • snow melting • salt dissolving in water • 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 Covalent bonds result from sharing electrons
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 More surface area!
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 Catalysts speeds up a chemical reaction by lowering the activation energy!
Which reaction type best describes the reaction above? A. Combination B. Decomposition C. Single replacement D. Combustion
1 3 1 3 ? AgNO3 + ?AlCl3 → ?AgCl + ?Al(NO3)3 Which of these sets of coefficients will balance this equation? A. 3, 3, 2, 1 B. 3, 1, 3, 1 C. 1, 6, 1, 9 D. 9, 3, 3, 3
The formula for lithium nitride is — A. LiN B. Li3N C. Li3N3 D. NLi3 Li+ N3-
This diagram of a chemical reaction shows that the reaction is — A. endothermic B. exothermic C. reversible D. at equilibrium More energy in products energy went into products
Ni(C2H3O2)4How many atoms are represented in this formula? A. 5 B. 8 C. 28 D. 29 1 + 4(2) + 4(3) + 4(2) = 29
The correct structural formula for C2H4 is Carbon forms 4 bonds! Only 2 hydrogen
What type of reaction does this illustration represent? A. Decomposition B. Synthesis C. Single-replacement D. Double-replacement AB A + B
Which of these reactions shows simple chemical decomposition? Synthesis Double Displacement Single Replacement
A compound has 50% sulfur and 50% oxygen. What is its empirical formula? Percent to mass Mass to mole Divide by small Multiply to whole
A compound has 50% sulfur and 50% oxygen. What is its empirical formula?
A compound has 50% sulfur and 50% oxygen. What is its empirical formula? • SO4 • S2O4 • SO3 • SO2
The Lewis electron dot system represents electrons in the — A. outer energy level B. inner level C. middle level D. core level X
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 Heat is a product therefore the reaction is …
The correct name for MgI2 is — A. magnesium iodide B. magnesium iodite C. magnesium (II) iodide D. magnesium diiodide Mg2+ Magnesium Ion I2 actually 2 I- Iodide ion
If the diagram were the correct representation for the Lewis structure of a molecule, then the X would be representative of the element — A. oxygen B. fluorine C. nitrogen D. sulfur Exception
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 7 dots = 7 valance electrons which is group 17
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
Change % to mass to moles divide by small 85.64 gC 1 mol C = 7.137 / 7.137 = 1 C 12 g C 14.36 g H 1 mol H = 14.36 / 7.137 = 2 H 1 g H Calculate the mass of the empirical formula CH2 1(12) + 2(1) = 14 Divide into molecular mass 42.08/14 = 3 Multiply by the empirical formula 3(CH2) = C3H6
Another way…. A. CH2 1(12) + 2(1) = 14 g B. C3H6 3(12) + 6(1) = 42 g C. C2H4 2(12) + 4(1) = 28 g D. C2H18 2(12) + 18(1) = 42 g The molar mass was 42 and there are two answers that are 42 but C2H18 is a formula that is not possible carbon only forms 4 bonds! Therefore B is the correct answer.
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 Highest BP and MP!
The empirical formula for ethyne (C2H2) is — A. CH B. C2H2 C. CH2 D. C2H Empirical formula = simplest formula
The type of reaction represented by the above equation is — A. single-replacement B. double-replacement C. synthesis D. decomposition
2 3 When this equation is correctly balanced, the coefficient of the AlCl3 will be — 2 3 A. 1 B. 2 C. 4 D. 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
Find Empirical FormulaChange % to massMass to MoleDividie by smallMultiply to wholeFind multiple of empirical formula to molecular formula by Mass
Or you can find the molar mass of each formula in answer choices and see which one equals 102…. C. C5H10O2 5(12) + 10(1) + 2(160) = 102 g
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 Example: 2Na + 2HOH 2NaOH + H2
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 Magnesium group 2 (metal) Chlorine group 17 (nonmetal)
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 Higher Temperature faster rate!