Chemistry test simple and complex substances

Content of the correct answer and guidelines for grading (other formulations of the answer are allowed without distorting its meaning)

Part A - 1 point 23-21 points - "5"Part B - 1 - 2 points 20-16 points - "4" 15 - 12 points - "3"

Bibliography:

Gabrielyan O.S., Chemistry. 8th grade. Bustard. 2010 Rudzitis G.E. Chemistry grade 8. M .: "Education", 2010.

TEST # 2 (1). Molecules and atoms. Simple and complex substances. Signs of chemical elements. Relative atomic and molecular weights. Chemical formulas.

Part A

Modern chemical symbols were developed by

1) D.I. Mendeleev 3) J. Berzelius

2) A. Lavoisier 4) A. Avogadro

2. A chemical element is

1) a certain kind of atoms

2) a substance that cannot be decomposed into simpler substances

3) atoms with the same mass

4) a substance that always increases its weight during chemical transformation.

3. The relative atomic mass of a chemical element is

1) the mass of its atom

2) the mass of its atom, expressed in amu.

3) the ratio of the mass of an atom to 1/12 of the mass of a carbon atom

4) the mass of its atom, expressed in grams

4. A simple substance is formed

1) identical molecules

2) atoms of one chemical element

3) molecules consisting of one atom

4) simple molecules

5. Molecular masses of Fe 3 O 4, H 3 PO 4, N 2 are equal respectively

6. The mass fraction of iron in the Fe 2 O 3 compound is

7. Mass fractions of elements in the combination of iron with sulfur are equal, respectively

46.67% and 53.33%. Compound formula

4) Fe 2 (SO 4) 3

Part B

8. Insert the missing words in the statement: “_________________________ is

the smallest chemically indivisible particles that make up the molecules. "

9. Establish a correspondence between the name of the substance and its type. Write down the answer

in the form of a sequence of letters and numbers, for example, A1, B2, etc.

1) water A - simple substances

2) oxygen B - complex substances

10. Divide into groups - metals (A) and non-metals (B) - chemical elements:

Write down the answer in the form of a sequence of letters and numbers, for example, A123, B456.

TEST # 2 (2). Molecules and atoms. Simple and complex substances. Signs of chemical elements. Relative atomic and molecular weights. Chemical formulas

Part A

The merit of introducing the concept of a chemical element into science belongs to

1. D. Dalton

   DI. Mendeleev

   Aristotle

Isotopes are

1. atoms of one chemical element

   atoms of one chemical element, differing in mass

   atoms of one chemical element, equal in mass

   atoms of one chemical element, the same size

The value given in the table of chemical elements by D.I. Mendeleev

the relative atomic mass of a chemical element is

the relative atomic mass of its heaviest isotope

the relative atomic mass of its lightest isotope

the relative atomic mass of its most abundant isotope in nature

average atomic mass of all isotopes, taking into account their abundance in nature

Nitrogen (N 2) is a simple substance, since its molecule

1. consists of two atoms

   contains few atoms

   contains identical atoms

   consists of atoms of one chemical element

The relative molecular weights of HNO 3, P 2 O 5, O 3 are respectively

1. The mass fraction of manganese in the Mn 2 O 7 compound is

2. The mass fractions of phosphorus and chlorine in the compound are 14.87% and 85.13%, respectively. Compound formula

Part B

1. Insert the missing words in the statement: “__________________________ is

atoms of the same kind. "

Establish a correspondence between the name of the substance and its type. Write the answer in

1) sulfur A - simple substances

2) oxygen B - complex substances

10. Divide into groups - metals (A) and non-metals (B) - chemical elements:

TEST # 3 (1). Valence of chemical elements. Drawing up formulas for valency. Chemical Equations... Types of chemical reactions.

Part A

The valences of sulfur, nitrogen and carbon in their hydrogen compounds (H 2 S, NH 3, CH 4) are respectively equal

2. Symbols of chemical elements that form simple substances-metals are written

under the number

3. The valence of sulfur in compounds Na 2 S, SO 3, CS 2 are equal, respectively

4. The formulas of binary compounds of calcium with nitrogen and aluminum with sulfur are respectively written under the number

Al 2 S 3, Ca 3 N 2

Ca 3 N 2, Al 2 S 3

Ca (NO 3) 2, Al 2 S 3

Ca 3 N 2, Al 2 (SO 4) 3

5. The sum of the coefficients in the reaction equation Na + H 2 O → NaOH + H 2 is

6. Complete the reaction equation (coefficients are indicated): Fe + CuCl 2 \u003d… + FeCl 2

formed from 5.6 g of iron and 3.2 g of sulfur.

Part B

8. Insert the words missing in the statement: “The mass of substances that entered into

chemical reaction ____________________ mass of the formed substances ".

Establish a correspondence between the left and right sides of the reaction equation.

Write down your answer in the form of a sequence of letters and numbers, for example, A1, B2, etc.

4Al + 3O 2 \u003d A. Al 2 O3 + 3H 2 O

2Al (OH) 3 \u003d B. 2AlCl 3 + 3H 2 O

Al 2 O 3 + 6HCl \u003d B. 2Al 2 O 3

Divide chemical reactions into groups - compounds (A) and substitutions (B):

4Fe + 3O 2 \u003d 2Fe 2 O 3

Hg (NO 3) 2 + Cu \u003d Cu (NO 3) 2 + HG

S + O 2 \u003d SO 2,

Zn + 2HCl \u003d ZnCl 2 + H 2

N 2 + O 2 \u003d 2NO

2Al (OH) 3 \u003d Al 2 O 3 + 3H 2 O

Write down the answer in the form of a sequence of letters and numbers, for example A123, B456.

TEST # 3 (2). Valence of chemical elements. Drawing up formulas for valency. Chemical equations. Types of chemical reactions.

Part A

The valence of calcium, sodium and aluminum in their compounds with oxygen - CaO, Na 2 O, Al 2 O 3 - is respectively equal to

1) I, II, III 3) II, I, III

2) III, II, I 4) II, III, I

2. Symbols of chemical elements forming simple substances - metals are written down

under the number

3. The valence of nitrogen in compounds Na 3 N, NO, NF 3 is, respectively, equal to

1) I, II, III 3) III, I, III

2) III, II, III 4) I, II, I

4. Formulas of binary compounds of magnesium with nitrogen and calcium with sulfur, respectively

recorded under number

1) CaS, Mg 3 N 2 3) Mg (NO 3) 2, CaS

2) Mg 3 N 2, CaSO 4 4) Mg 3 N 2, CaS

5. The sum of the coefficients in the reaction equation FeCl 2 + Cl 2 → FeCl 3 is

6. Complete the reaction equation (coefficients are indicated): Mg + 2… \u003d H 2 + MgCl 2

7. Using the law of conservation of mass, determine the mass of iron (II) sulfide,

formed from 56 g of iron and 32 g of sulfur.

Part B

8. Insert the missing words in the statement: "_________________________ call

conventional representation of the course of a chemical reaction by means of signs and formulas. "

9. Establish a correspondence between the left and right sides of the reaction equation. Write down your answer in the form of a sequence of letters and numbers, for example, A1, B2, etc.

1) 4Fe + 3O 2 \u003d A. Fe 2 O 3 + 3H 2 O

2) 2Fe (OH) 3 \u003d B. 2FeCl 3 + 3H 2 O

3) Fe 2 O 3 + 6HCl \u003d B. 2Fe 2 O 3

10. Distribute the chemical reactions into groups - decomposition (A) and substitution (B):

1) 4Fe + 3O 2 \u003d 2Fe 2 O 3

2) Hg (NO 3) 2 + Cu \u003d Cu (NO 3) 2 + Hg

3) 4HNO 3 \u003d 4NO 2 + O 2 + 2H 2 O

4) Zn + 2HCl \u003d ZnCl 2 + H 2

5) CaCO 3 \u003d CaO + CO 2

6) Al (OH) 3 \u003d Al 2 O 3 + 3H 2 O

Write down the answer in the form of a sequence of letters and numbers, for example A123, B456.

TEST # 4 (1). Molar mass. Calculations by equations of chemical reactions

Part A

What is the number of water molecules contained in a 3.6 g portion of a substance?

1. Molar mass of compound CuSO 4 ∙ 5H 2 O (g / mol)

2. What is the amount of substance (mol) contained in sulfur (VI) oxide with a mass of 12 g?

3. When a solution containing sodium hydroxide NaOH weighing 4 g interacts with a solution of copper (II) chloride Cu (OH) 2 and sodium chloride NaCl. What is the mass (g) of the oxide? (Give your answer as an integer.)

4. What is the mass (g) of iron (III) chloride obtained by the reaction of 16.8 g iron with chlorine?

5. What is the mass (g) of iron oxide Fe 3 O 4, formed during the combustion of iron in air weighing 11.2 g?

6. The mass of the precipitate of barium sulfate BaSO 4 formed when mixing solutions containing sodium sulfate Na 2 SO 4 weighing 1.42 g and barium chloride BaCl 2 weighing 2.8 g is

7. What is the mass of the aluminum chloride salt AlCl 3 (g) formed as a result of the reaction of aluminum hydroxide Al (OH) 3 weighing 23.4 g and of hydrochloric acid HCl containing 35 g of hydrogen chloride?

Part B

1. Calculate the mass of iron (III) oxide formed by the reaction of 22.4 g of iron with 10 g of oxygen. Give your answer as an integer.

   When methane (CH 4) burns in air, carbon dioxide and water are formed. Calculate the mass of air required for combustion of 16 g of methane if the mass fraction of oxygen in the air is 28.6%.

TEST # 4 (2). Molar mass. Calculations by the equations of chemical reactions.

Part A

What is the number of phosphorus atoms in a 155 g sample of phosphorus?

1. Molar mass of compound CaSO 4 ∙ 2H 2 O (g / mol)

2. The mass of a sulfur sample is 19.2 g. What is the amount of sulfur (mol)?

3. What is the mass (g) of sodium carbonate Na 2 CO 3 equal to the amount of substance 0.25 mol?

4. The interaction of a solution containing sodium hydroxide NaOH weighing 8 g with a solution of copper (II) nitrate Cu (NO 3) 2 formed a precipitate of copper (II) hydroxide Cu (OH) 2 and sodium nitrate (NaNO 3). What is the mass (g) of copper (II) hydroxide? (Give your answer as an integer.)

5. What is the mass of sulfur (g), which has reacted with aluminum weighing 2.7 g?

6. What is the mass of iron (III) hydroxide (g), dissolved in sulfuric acid H 2 SO 4, weighing 9.8 g? Reaction scheme: Fe (OH) 3 + H 2 SO 4 → Fe 2 (SO 4) 3 + H 2 O. (Give the answer as an integer).

8. What is the mass of the precipitate of barium sulfate BaSO 4 (g) formed upon mixing?

solutions containing sodium sulfate Na 2 SO 4 weighing 1.6 g and barium chloride BaCl 2

weighing 2.08 g?

Part B

9. Calculate the mass of copper (II) oxide formed by the interaction of 27 g of aluminum with

25 g oxygen. Give your answer as an integer.

When methane (CH 4) burns, carbon dioxide and water are formed. Calculate the mass of air required to burn 32 g of methane if the mass fraction of oxygen in the air is 28.7%.

Final (thematic) control test

TEST No. 1 (1). Generalization and control of knowledge on the topic "Initial chemical concepts"

Part A

To separate a mixture of chalk and table salt powders,

1. use a magnifying glass and tweezers

   add water to the mixture, then filter

   pass the mixture through a sieve

   add water to the mixture, then filter and evaporate the filtrate

The list of pure substances is placed under the number

1. distilled water, aluminum, air

   soil, sea water, perfume

   copper, iron, lead

   steel, bronze, cupronickel

1. sour milk and candle burning

   melting ice and evaporation of water

   freezing of water and rotting residues

   light bulb glow and cloud formation

Formulas of only simple substances

1. PH 3, P 4, O 3

   NH 3, N 2, N 2 O

2. H 2 O, Cl 2, HCl

The ammonia molecule consists of

1. three nitrogen atoms and one hydrogen atom

   one nitrogen atom and three hydrogen atoms

   one nitrogen atom and one hydrogen atom

   three nitrogen atoms and three hydrogen atoms

The sum of the coefficients in the equation for the reaction of phosphorus (P) with an excess of oxygen (О 2)

The valence of chromium in the Cr 2 O 3 compound is

1. The mass fraction of zinc in zinc chloride is

Part B

A. Atoms are the smallest, chemically indivisible particles that make up molecules.

B. In physical phenomena, the molecules of a substance are preserved, and in chemical phenomena, they are destroyed.

1) both statements are true

2) statement A is true, statement B is incorrect

3) statement B is true, statement A is incorrect

4) both statements are wrong

10. Establish a correspondence between the reaction equation and its type. Write the answer in

the form of a sequence of letters and numbers, for example, A1, B2, etc.

Fe 2 O 3 + 6HCl \u003d 2FeCl 3 + 3H 2 O A. Substitution

Fe + 2HCl \u003d FeCl 2 + H 2 B. Compound

4Fe + 3O 2 \u003d 2Fe 2 O 3 V. Decomposition

2Fe (OH) 3 \u003d Fe 2 O 3 + 3H 2 O G. Exchange

TEST # 1 (2). Generalization and control of knowledge on the topic "Initial chemical concepts"

Part A

A mixture of sulfur and iron powders can be separated using

1. filtering

2. decantation

   distillation

The list of mixtures is placed under the number

1. sugar, iron, air

   soil, sea water, perfume

   copper, bronze, lead

   steel, oxygen, cupronickel

Only chemical phenomena are described under the number

1. charring sugar and sugaring jam

   frost and cloud formation

   sour milk and gas evolution from a bottle of lemonade

   gas formation when mixing soda with vinegar and blackening of silver items

Formulas of only simple substances are combined under a number

2. S 8, P 4, NH 3

3. NaOH, KOH, HNO 3

Sulfur (IV) oxide molecule consists of

1. one sulfur atom and one oxygen atom

   one sulfur atom and three oxygen atoms

   one sulfur atom and two oxygen atoms

   two sulfur atoms and one oxygen atom

The sum of the coefficients in the equation for the reaction of aluminum with oxygen (О 2) is

1. The valence of chromium in the CrO 3 compound is

2. Mass fraction of calcium in calcium nitride is

Part B

1. Give your opinion on the judgments:

A. The molecules of substances are in continuous motion. Travel speed

molecules depends on temperature.

B. In physical phenomena, the molecules of a substance are destroyed, and in chemical phenomena,

persist.

both statements are correct

statement A is true, statement B is incorrect

statement B is true, statement A is incorrect

both statements are wrong

Establish a correspondence between the reaction equation and its type. Write the answer in

the form of a sequence of letters and numbers, for example, A1, B2, etc.

Al 2 O 3 + 6HCl \u003d 2AlCl 3 + 3H 2 O A. Substitution

2Al + 6HCl \u003d 2AlCl 3 + 3H 2 B. Compound

4Al + 3O 2 \u003d 2Al 2 O 3 V. Decomposition

2Al (OH) 3 \u003d Al 2 O 3 + 3H 2 O G. Exchange

• generalize knowledge on the topic “Simple and complex substances”;
• the formation of students' communication skills when working in groups.

Equipment:

• Tablets with a menu for each table - 4 pcs .;
• Map for assessing the student's contribution to the work of the group;
• Description of tasks (according to the menu) for students on each table - 4 pcs.
• Credit in the amount of 40 USD
• PSCE and solubility table.

Students visit a cafe. 3 groups of 4 people are formed, each group chooses the responsible (administrator) table. During the game, the work of each group is evaluated by both the teacher and classmates (opponents).

In the menu instead of the usual dishes, tasks on the topic are presented. Each group received a loan in the amount of 40 USD. When solving tasks, students receive an estimate in cu.

Students' performance is assessed according to the following scheme:

“Excellent” - $ 1, “good” - $ 2; "Satisfactory" - 3 cu

The number of received c.u. is deducted from this loan. The winner is the group with the highest total.

During the game, each participant must perform at least 1 time.

The game is played in several stages:

1. "Cold snacks"

• Crossword;
• Definition of terms;
• Distribution of substances by class.

2. "Hot dishes"

• Draw up formulas of substances;
• Give names to substances;
• Solve the problem using the formula.

3. "Drinks"

• Test number 1.

4. "Spirits"

Test number 2: 4 options.

5. "Dessert"

Guessing riddles.

Map for assessing the student's contribution to the work of the group (carried out on a 5-point scale)

Good day! I am glad to welcome you to the chemical cafe Firefly! The aim of our cafe will be to summarize the topic “Simple and complex substances”. Each of you has taken his own table, and I suggest you choose a table administrator - who will coordinate the work of his table.

I ask you to familiarize yourself with the menu. In it, instead of ordinary dishes, tasks on the topic are presented. Everyone needs to answer at least once.

Dessert tasks:

1. What is called white gold? ( Cotton.)
2. What chemical is the name of the soup with beets and other vegetables? ( B - borsch.)
3. What is called "living silver"? ( Fish.)
4. What is the name of the fur of fur animals? ( Fluffy gold.)
5. Throw out the 4th letter in the name of a mountain antelope, and you get the name of a chemical element of group 6. ( Chamois is sulfur.)
6. It begins with a small rodent, ends with a bull, as chemical element called? ( Arsenic.)
7. What chemical element “calls” a cat to visit? ( Oxygen.)