chem 16 first long exam

8/10/2019 Chem 16 First Long Exam

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CHEM 16 LABFIRST LONG EXAM

I. Give the name or symbol of the following:1. CoCl2

2. Fe4(PO4)3

3.

(NH)S4. CuBr5. PO6. ammonium dichromate

7. xenon difluroide

8. copper(II) sulfate pentahydrate9. auric chloride

10.boric acid

II. Match each of the following with the correct definition.____ 1. Matter

____ 2. Heterogeneous mixture____ 3. Density____ 4. Compound

____ 5. Molecule

____ 6. Viscosity____ 7. Element

____ 8. Pure substance

____ 9. 1.0 g/mL____ 10. Mass

A. a substance with one or more identical

atomsB. the units for densityC. a measure of a fluids resistance to flow

(how thick it is)

D. a measurement of the total amount ofmatter in an object

E. anything that has mass and volume (takes

up space)F. the density of liquid waterG. a mixture of substances that are not easily

recognizable

H. a measurement of how compact asubstance is (mass volume)I. any substance with a fixed ratio of

elements

J. 2 or more atoms of the same elementsbonded; Ex: O2, H2, Cl2

K. a mixture of substances which are easily

recognizableL. a substance consisting of 2 or more atoms

from different elements

III.

Identify each example of matter as either a Pure Substance (PS) or Mixture (M).

1. Salt water _____

2. Chicken Noodle soup _____3. Salt _____

4. Silver _____

5. Helium _____


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IV.Identify each of the following as a physical property (PP), physical change (PC), chemical

property (CP), or chemical change (CC).

1. Sharpening your pencil. _____ 6. Flammability _____

2. A density of 0.9 g/mL. _____ 7. A bicycle rusting. _____

3. Boiling water. _____ 8. An explosion. _____4. Copper reacting with hydrochloric acid. _____ 9. Cutting a piece of food. _____5. Forming water by burning hydrogen. _____ 10. Viscosity _____

V. Write the letter of the correct answer.

.

____ 1. A substance that enters into a chemical reaction is called a

a. mole. c. coefficient.b. product. d. reactant.

____ 2. In a reaction in which hydrogen reacts with oxygen to produce water, which substancesare the reactants?

a. hydrogen only c. both hydrogen and oxygen

b. oxygen only d. water

____ 3. Which of the following is not an example of a chemical change?

a. rusting iron c. cutting paper

b. an apple ripening d. a piece of wood burning

____ 4. In a chemical equation, the symbol that takes the place of the words reacts with is a(n)

a. equal sign. c. plus sign.

b. coefficient. d. arrow.

____ 5. In a chemical equation, the symbol that takes the place of the word yields is a(n)

a. equal sign. c. plus sign.b. coefficient. d. arrow.

____ 6. When oxygen is available, sulfur dioxide is produced from the burning of sulfur. Whichof the following word equations best represents this reaction?

a. sulfur + oxygensulfur dioxide

b. sulfur dioxide + oxygensulfur

c. sulfur dioxidesulfur + oxygend. sulfursulfur dioxide + oxygen

____ 7. The word equation magnesium reacts with chlorine to produce magnesium chloride

would be represented by which of the following formula equations?a. MgCl2+ MgCl2

b. MgCl2Mg+ Cl2

c. MgCl2+ MgCl2d. Mg + Cl2MgCl2


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____ 8. Which of the following is true of a balanced equation?

a. The number of atoms per molecule remains the same.

b. The kinds of atoms remain the same.c. The total number of molecules remains the same.

d. The number of atoms of each element remains the same

____ 9. In a chemical reaction, what is the relationship between the total mass of the reactantsand the total mass of the products?

a. They must be equal.

b. The mass of the products must be greater.c. The mass of the reactants must be greater.

d. There is no general relationship between the two.

____ 10. In a chemical equation, the number of molecules of a given substance is indicated by aa. subscript. c. superscript.

b. coefficient. d. reaction number.

____ 11. How many atoms of oxygen are represented in 2 Ca(NO3)2?

a. 4 c. 10

b. 6 d. 12

____ 12. In balancing a chemical equation, which of the following are you allowed to do?

a. change subscripts c. change superscripts

b. write coefficients d. add new substances

____ 13. The symbol (s) written after a formula in a chemical equation stands for

a. soluble. c. solid.

b. solution. d. synthesis.

____ 14. Which of the following symbols means a substance is in water solution?

a. (aq) c. (w)b. (s) d. (l)

____ 15. What is the general form for a single-replacement reaction?a. AX + BYAY + BX c. A + BAB

b. ABA + B d. A + BXAX + B

____ 16. What is the general form for a double-replacement reaction?a. AX + BYAY + BX c. A + BAB

b. ABA + B d. A + BXAX + B

____ 17. What kind of reaction is represented by the equation C2Cl4+ Cl2C2Cl6?a. synthesis c. single replacement

b. double replacement d. combustion


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____ 18. A chemical reaction has NOT occurred if the products have

a. the same mass as the reactants.

b. less total bond energy than the reactants.c. more total bond energy than the reactants.

d. the same chemical properties as the reactants.

____ 19. Which observation does NOT indicate that a chemical reaction has occurred?a. formation of a precipitate c. evolution of heat and light

b. production of a gas d. change in total mass of substances

____ 20. A solid produced by a chemical reaction in solution that separates from the solution is

called

a. a precipitate. c. a molecule.

b. a reactant. d. the mass of the product.

____ 21. After the correct formula for a reactant in an equation has been written, the

a. subscripts are adjusted to balance the equation.b. formula should not be changed.

c. same formula must appear as the product.

d. symbols in the formula must not appear on the product side of the equation.

____ 22. In writing an equation that produces hydrogen gas, the correct representation of

hydrogen gas is

a. H. c. H2.b. 2H. d. OH.

____ 23. To balance a chemical equation, it may be necessary to adjust the

a. coefficients. c. formulas of the products.b. subscripts. d. number of products.

____ 24. According to the law of conservation of mass, the total mass of the reacting substancesis

a. always more than the total mass of the products.

b. always less than the total mass of the products.c. sometimes more and sometimes less than the total mass of the products.

d. always equal to the total mass of the products.

____ 25. For the formula equation 2Mg + O22MgO, the word equation would begina. Manganese plus oxygen c. Magnesium plus oxygen

b. Molybdenum plus oxygen d. Heat plus oxygen

____ 26. After the first steps in writing an equation, the equation is balanced bya. adjusting subscripts to the formula(s).

b. adjusting coefficients to the smallest whole-number ratio.

c. changing the products formed.d. making the number of reactants equal to the number of products.


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____ 27. The reaction 2Mg(s) + O2(g)2MgO(s) is a

a. synthesis reaction. c. single-replacement reaction.

b. decomposition reaction. d. double-replacement reaction.

____ 28. The reaction Mg(s) + 2HCl(aq)H2(g) + MgCl2(aq) is a

a. composition reaction. c. single-replacement reaction.b. decomposition reaction. d. double-replacement reaction.

____ 29. The reaction 2HgO(s)2Hg(l) + O2(g) is a(n)

a. single-replacement reaction. c. ionic reaction.b. synthesis reaction. d. decomposition reaction.

____ 30. The reaction Pb(NO3)2(aq) + 2KI(aq)PbI2(s) + 2KNO3(aq) is a

a. double-replacement reaction. c. decomposition reaction.b. synthesis reaction. d. combustion reaction.

____ 31. The reaction 2KClO3(s)

2KCl(s) + 3O2(g) is a(n)a. synthesis reaction. c. combustion reaction.

b. decomposition reaction. d. ionic reaction.

____ 32. In one type of synthesis reaction, an element combines with oxygen to yield a(n)a. acid. c. oxide.

b. hydroxide. d. metal.

____ 33. When a binary compound decomposes, what is produced?

a. an oxide c. a tertiary compound

b. an acid d. two elements

____ 34. In the equation 2Al(s) + 3Fe(NO3)2(aq)3Fe(s) + 2Al(NO3)3(aq), iron has been

replaced by

a. nitrate. c. aluminum.b. water. d. nitrogen.

____ 35. In a double-replacement reaction, hydrogen chloride and sodium hydroxide react toproduce sodium chloride. Another product is

a. sodium hydride. c. water.

b. potassium chloride. d. hydrogen gas.

VI. Answer briefly. Show calculations if needed.

1. A student wishes to determine the density of an irregularly shaped fishing weight to

determine if it is made from a pure metal, lead in this case, or an alloy. Describe a

practical process, utilizing common lab equipment, by which this measurement could bemade. The student discovers that the density of the object is 11.30 g/cm3, and concludes


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that it is indeed made from pure lead (leads density is reported to be 11.34 g/cm3 at

room temperature). Discuss the validity of the claim and possible sources of error that

would invalidate the conclusions made.

2. Classify the following as either physical or chemical changes, and provide a brief

explanation for each choice:a) A tires tread wears down with use.b) An iron poker in a fire begins to glow red.

c) A mixture of amino acids is combined to create a protein.

d) White, mineral-like deposits form at the end of a faucet.e) Antacid tablets fizz when dropped into a glass of water.

3. Write 7 reactions observed in Experiment 2 (Chemical Changes) and Experiment 3

(Classification of Matter)

4. Discuss one technique in the laboratory (Experiment 0)

Bonus:

What is the name of the CAS building?

SOTECH was once part of what acad-org?

What is the undergraduate course of the UP President?

What is my cellphone number?

CACatalan

OCT 2014

chem 16 first long exam

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