Atoms: The Building Blocks of Matter - David Brearley High School

Loading...

Name

Date

Class

CHAPTER 3 REVIEW

Atoms: The Building Blocks of Matter SECTION 1 SHORT ANSWER

Answer the following questions in the space provided.

1. Why is Democritus’s view of matter considered only an idea, while Dalton’s view is considered a theory? Democritus’s idea of matter does not relate atoms to a measurable property, while Dalton’s theory can be tested through quantitative experimentation.

2. Give an example of a chemical or physical process that illustrates the law of conservation of mass. A glass of ice cubes will have the same mass when the ice has completely melted into liquid water, even though its volume will change. (Accept any reasonable process.)

3. State two principles from Dalton’s atomic theory that have been revised as new information has become available. Atoms are divisible into smaller particles called subatomic particles. A given element can have atoms with different masses, called isotopes.

4. The formation of water according to the equation 2H2  O2 → 2H2O shows that 2 molecules (made of 4 atoms) of hydrogen and 1 molecule (made of 2 atoms) of oxygen produce 2 molecules of water. The total mass of the product, water, is equal to the sum of the masses of each of the reactants, hydrogen and oxygen. What parts of Dalton’s atomic theory are illustrated by this reaction? What law does this reaction illustrate? Atoms cannot be subdivided, created, or destroyed. Also, atoms of different elements combine in simple, whole-number ratios to form compounds. The reaction also illustrates the law of conservation of mass.

MODERN CHEMISTRY Copyright © by Holt, Rinehart and Winston. All rights reserved.

ATOMS: THE BUILDING BLOCKS OF MATTER

17

Name

Date

Class

SECTION 1 continued

PROBLEMS provided. 5.

Write the answer on the line to the left. Show all your work in the space

16 g

If 3 g of element C combine with 8 g of element D to form compound CD, how many grams of D are needed to form compound CD2?

6. A sample of baking soda, NaHCO3, always contains 27.37% by mass of sodium, 1.20% of hydrogen, 14.30% of carbon, and 57.14% of oxygen. a. Which law do these data illustrate? the law of definite proportions b. State the law. A chemical compound contains the same elements in exactly the same proportions by mass regardless of the sample or the source of the compound.

7. Nitrogen and oxygen combine to form several compounds, as shown by the following table. Compound

Mass of nitrogen that combines with 1 g oxygen (g)

NO

1.70

NO2

0.85

NO4

0.44

Calculate the ratio of the masses of nitrogen in each of the following: NO NO2 NO 2.0 a.  2.0 b.  4.0 c.     NO2 NO4 NO4

d. Which law do these data illustrate? the law of multiple proportions

18

ATOMS: THE BUILDING BLOCKS OF MATTER

MODERN CHEMISTRY Copyright © by Holt, Rinehart and Winston. All rights reserved.

Name

Date

Class

CHAPTER 3 REVIEW

Atoms: The Building Blocks of Matter SECTION 2 SHORT ANSWER

Answer the following questions in the space provided.

1. In cathode-ray tubes, the cathode ray is emitted from the negative electrode, which is called the cathode

.

2. The smallest unit of an element that can exist either alone or in molecules containing the same or different elements is the

atom

.

3. A positively charged particle found in the nucleus is called a(n) 4. A nuclear particle that has no electrical charge is called a(n)

proton neutron

. .

5. The subatomic particles that are least massive and most massive, respectively, are the electron

and

neutron

.

6. A cathode ray produced in a gas-filled tube is deflected by a magnetic field. A wire carrying an electric current can be pulled by a magnetic field. A cathode ray is deflected away from a negatively charged object. What property of the cathode ray is shown by these phenomena? The particles that compose cathode rays are negatively charged. 7. How would the electrons produced in a cathode-ray tube filled with neon gas compare with the electrons produced in a cathode-ray tube filled with chlorine gas? The electrons produced from neon gas and chlorine gas would behave in the same way because electrons do not differ from element to element.

8. a. Is an atom positively charged, negatively charged, or neutral? Atoms are neutral. b. Explain how an atom can exist in this state. Atoms consist of a positively charged nucleus, made up of protons and neutrons, that is surrounded by a negatively charged electron cloud. The positive and negative charges combine to form a net neutral charge.

MODERN CHEMISTRY Copyright © by Holt, Rinehart and Winston. All rights reserved.

ATOMS: THE BUILDING BLOCKS OF MATTER

19

Name

Date

Class

SECTION 2 continued

9. Below are illustrations of two scientists’ conceptions of the atom. Label the electrons in both illustrations with a  sign and the nucleus in the illustration to the right with a  sign. On the lines below the figures, identify which illustration was believed to be correct before Rutherford’s goldfoil experiment and which was believed to be correct after Rutherford’s gold-foil experiment.

a.

(Students should place a  sign inside all circles.) a. before Rutherford’s experiment

b.

(Students should place a  sign in the center and a  sign inside all circles.) after Rutherford’s experiment b.

10. In the space provided, describe the locations of the subatomic particles in the labeled model of an atom of nitrogen below, and give the charge and relative mass of each particle.

a.

b.

c.

a. proton The proton, a positive and relatively massive particle, should be located in the nucleus.

b. neutron The neutron, a neutral and relatively massive particle, should be located in the nucleus.

c. electron (a possible location of this particle) The electron, a negative particle with a low mass, should be located in the cloud surrounding the nucleus.

20

ATOMS: THE BUILDING BLOCKS OF MATTER

MODERN CHEMISTRY Copyright © by Holt, Rinehart and Winston. All rights reserved.

Name

Date

Class

CHAPTER 3 REVIEW

Atoms: The Building Blocks of Matter SECTION 3 SHORT ANSWER

Answer the following questions in the space provided.

1. Explain the difference between the mass number and the atomic number of a nuclide. Mass number is the total number of protons and neutrons in the nucleus of an isotope. Atomic number is the total number of protons in the nucleus of each atom of an element.

2. Why is it necessary to use the average atomic mass of all isotopes, rather than the mass of the most commonly occurring isotope, when referring to the atomic mass of an element? Elements rarely occur as only one isotope; rather, they exist as mixtures of different isotopes of various masses. Using a weighted average atomic mass, you can account for the less common isotopes.

3. How many particles are in 1 mol of carbon? 1 mol of lithium? 1 mol of eggs? Will 1 mol of each of these substances have the same mass? There are 6.022  1023 particles in 1 mol of each of these substances. One mole of one substance will not necessarily have the same mass as one mole of another substance. 4. Explain what happens to each of the following as the atomic masses of the elements in the periodic table increase: a. the number of protons increases b. the number of electrons increases c. the number of atoms in 1 mol of each element stays the same

MODERN CHEMISTRY Copyright © by Holt, Rinehart and Winston. All rights reserved.

ATOMS: THE BUILDING BLOCKS OF MATTER

21

Name

Date

Class

SECTION 3 continued

5. Use a periodic table to complete the following chart: Element

Symbol

Atomic number

Mass number

Europium-151

151 63Eu

63

151

Silver-109

109 47Ag

47

109

Tellurium-128

128 52Te

52

128

6. List the number of protons, neutrons, and electrons found in zinc-66. 30

protons

36

neutrons

30

electrons

PROBLEMS provided.

Write the answer on the line to the left. Show all your work in the space

7.

32.00 g

8.

3.706 mol

9.

1.994  1024 atoms

10.

1.993  1021 g

22

What is the mass in grams of 2.000 mol of oxygen atoms?

How many moles of aluminum exist in 100.0 g of aluminum?

How many atoms are in 80.45 g of magnesium?

What is the mass in grams of 100 atoms of the carbon-12 isotope?

ATOMS: THE BUILDING BLOCKS OF MATTER

MODERN CHEMISTRY Copyright © by Holt, Rinehart and Winston. All rights reserved.

Name

Date

Class

CHAPTER 3 REVIEW

Atoms: The Building Blocks of Matter MIXED REVIEW SHORT ANSWER

Answer the following questions in the space provided.

1. The element boron, B, has an atomic mass of 10.81 amu according to the periodic table. However, no single atom of boron has a mass of exactly 10.81 amu. How can you explain this difference? The periodic table reports the average atomic mass, which is a weighted average of all isotopes of boron.

2. How did the outcome of Rutherford’s gold-foil experiment indicate the existence of a nucleus? A few alpha particles rebounded and therefore must have “hit” a dense bundle of matter. Because such a small percentage of particles were redirected, he reasoned that this clump of matter, called the nucleus, must occupy only a small fraction of the atom’s total space.

3. Ibuprofen, C13H18O2, that is manufactured in Michigan contains 75.69% by mass carbon, 8.80% hydrogen, and 15.51% oxygen. If you buy some ibuprofen for a headache while you are on vacation in Germany, how do you know that it has the same percentage composition as the ibuprofen you buy at home? The law of definite proportions states that a chemical compound contains the same elements in exactly the same proportions by mass regardless of the site of the sample or the source of the compound.

4. Complete the following chart, using the atomic mass values from the periodic table: Compound

Mass of O (g)

Ratio of O:Fe

55.85

16.00

0.2865

Fe2O3

111.70

48.00

0.4297

Fe3O4

167.55

64.00

0.3820

FeO

Mass of Fe (g)

MODERN CHEMISTRY Copyright © by Holt, Rinehart and Winston. All rights reserved.

ATOMS: THE BUILDING BLOCKS OF MATTER

23

Name

Date

Class

MIXED REVIEW continued

5. Complete the following table: Element

Symbol

Atomic number

Sodium

Na

11

22

11

11

11

Fluorine

F

9

19

9

10

9

Bromine

Br

35

80

35

45

35

Calcium

Ca

20

40

20

20

20

Hydrogen

H

1

1

1

0

1

Radon

Rn

86

222

86

PROBLEMS provided. 6.

Mass number

Number of protons

Number of neutrons

136

Number of electrons

86

Write the answer on the line to the left. Show all your work in the space

1.51  1024 atoms

a. How many atoms are there in 2.50 mol of hydrogen?

1.51  1024 atoms

b. How many atoms are there in 2.50 mol of uranium?

4.65 mol

c. How many moles are present in 107 g of sodium?

7. A certain element exists as three natural isotopes, as shown in the table below. Isotope

Mass (amu)

Percent natural abundance

Mass number

1

19.99244

90.51

20

2

20.99395

0.27

21

3

21.99138

9.22

22

20 amu

24

Calculate the average atomic mass of this element.

ATOMS: THE BUILDING BLOCKS OF MATTER

MODERN CHEMISTRY Copyright © by Holt, Rinehart and Winston. All rights reserved.

Loading...

Atoms: The Building Blocks of Matter - David Brearley High School

Name Date Class CHAPTER 3 REVIEW Atoms: The Building Blocks of Matter SECTION 1 SHORT ANSWER Answer the following questions in the space provided...

224KB Sizes 55 Downloads 20 Views

Recommend Documents

Atoms: The Building Blocks of Matter
Sep 29, 2016 - Section Quiz: The Atom: From Philosophical. Idea to Scientific Theory. In the space provided, write the l

moles to mass-to particles.pdf - David Brearley High School
A Ae to copygions Worksheet A/V State Aze Nae. Define one mole of a substance as 6.02 X 10° particles. High MoL3 Define

Atoms: Building Blocks of Molecules | Of Particular Significance
Dec 7, 2012 - We use the equations of quantum mechanics to describe and predict the behavior of molecules, atoms, and su

The building blocks of high- performing primary care
Apr 29, 2008 - Empanelment and panel size management. • Empanelment = linking patients with a primary care clinician/t

Atoms and Matter - ThatQuiz
B) atom table. C) element table. 14. The ______ ______ represents the number of protons and electrons. A) Molecule B) At

Building Blocks of Geometry
L E S S O N. 1.1. Building Blocks of Geometry. Three building blocks of geometry are points, lines, and planes. A p

Foundations.Chemistry.Chptr.resources.pdf | Matter | Atoms - Scribd
Student Lab Safety Form. 5. all students. Launch Lab. 8. 25. 47. 66. all students. Content Vocabulary ELL. 9. 26. 48. 67

Computing - The King David High School
Unit 27 – Digital Graphics; Unit 28 – Networked Systems Security; Unit 29 – The Business Environment; Unit 30 –

Building Blocks Competition
Riley Falconer. 19. PHS. 38.4. 384. 14. Jose Zarate, Daniel Ruiz, Simon Barrera. 3 ... Azucena Izquierdo, Charlie Hernan

Building Blocks VFIS - VFIS.com
Apr 9, 1996 - Guidelines on writing newspaper articles profiling volunteers . ..... We can call these statements––st