This document is a chemistry examination from Naawan National High School. It contains multiple choice and short answer questions testing knowledge of basic chemistry concepts including: - Molecular motion and gas properties such as diffusion and pressure - Composition of air and the atmosphere - Behavior of gases including pressure, volume, and temperature relationships - Atomic structure including protons, neutrons, electrons, isotopes, and electron configuration - Use of the periodic table to determine elemental properties The exam also tests understanding of the contributions of scientists like Thomson, Dalton, and Chadwick to the development of atomic theory and discovery of subatomic particles. Key terms involving atomic and molecular structure are defined.

1. Department of Education
Region X
Division of Misamis Oriental
NAAWAN NATIONAL HIGH SCHOOL
Linangkayan, Naawan, Misamis Oriental
Chemistry
Third Periodical Examination
Name: ___________________________________ Score: ___________________
Year and Section: __________________________ Date: ____________________
I. Write the letter of the correct answer before the number.
_D_01. Which observation does not show molecular motion?
A. A drop of milk in a cup of coffee slowly spreads without stirring
B. Smell of garlic being cooked in the kitchen reaches your nose
C. Acetone disappears from the bottle after some time
D. None of the above
_A_ 02. Gas A travels a distance of 4.0 cm in air. Gas B travels a distance of 12.0 cm in the same interval of time. What is
the ratio of speeds of diffusion of gases A and B in air?
A. 1:3 B. 3:1 C. 1:4 D. 3:4
_D_ 03. Which statement is true?
A. Air is a compound. B. Air supply is unlimited.
C. Air is mostly oxygen gas. D. Air is a homogeneous mixture.
___D__ 04. Which statement is not true?
A. Gases can diffuse easily. B. Air is colorless, tasteless, and odorless.
B. Gases have no definite shape or volume. D. Air cannot be separated into its components.
___D__ 05. The atmosphere is made up of different gases. Which gas, present in very small percentage, do plants use?
A. Argon B. Oxygen C. Nitrogen D. Carbon dioxide
__C___ 06. Which of the following statements describes the pressure of a gas in a container?
A. The volume of the gas in the container. B. The number of gas particles in a container
C. The force exerted by the gas particles in the container D. The value of pressure is 760 mmHg
__B___ 07. An air pump is used to bring back the original shape of a bicycle tire. What will happen to the volume of
attire when air is added to it?
A. The tire expands because its volume increases. B. The amount of air particles increases; thus the volume increases.
C. The air particles leak out; thus the volume decreases. D. The tire’s shape remains the same; thus there is no
change in the volume.
For Qs 8-11, kindly refer to the choices below:
A. Gases exert equal pressure in all directions.
B. Gases can be compressed.
C. Gases expand when heated and contract when cooled.
D. Molecules of gases move randomly called diffusion.
E. Gases occupy space.
__A or E___ 08. Why do you think the balloon is equally inflated?
__C___ 09. Why do balloons become bigger when heated and smaller when cooled?
__D___ 10. Why can you smell the fried tuyo cooked in the neighborhood?
E _ 11. What activity shows that gases occupy space?
__B_ 12. How will you interpret when two gases diffuse on a wet paper with solution C in a tube at a fixed length? It was
observed that it took 1 minute for gas A to form the pinkish color and 3 minutes for gas B. How would you explain this?
A. Gas A has a greater particle mass than gas B. B. Gas A has less particle mass than gas B.
C. Gas A particle travels more slowly. D. None of these
__B__ 13. During summer, tourists travel very long distances from Iligan to Davao. The pressure of the air in the tire of a
tourist bus is greatly affected. Why?
A. Because the temperature is constant B. Because as the pressure increases, the temperature
increases
C. Because as the pressure decreases, the temperature increases D. None of the above
__B__ 14. The atomic number of an element is equal to the number of _____ in the nucleus.
A. Electrons B. protons C. neutrons D. mesons
__A__ 15. The number of protons of an atom is equal to the number of
A. Electrons B. protons C. neutrons D. mesons

2. __C___ 16. The total number of protons and neutrons in the nucleus is equal to
A. Atomic number B. mole C. mass number D. formula mass
__C___ 17. Atoms that have the same number of protons but different number of neutrons are called
A. Molecules B. diatomic C. isotopes D. mole
__A or B___ 18. The sub atomic particles are responsible for the chemical behavior of
A. Atom B. element C. molecule D. mole
__A___ 19. It is the region where the electrons are most likely located.
A. Orbital B. wave C. nucleus D. vacuum
___B__ 20. It is the state of an atom where it is in its greatest stability but lowest energy level.
A. Excited B. ground C. quantum D. balanced
___D__ 21. How many orbital are there in the p orbital?
A. 1 B. 7 C. 4 D. 3
__B___ 22. How many electrons can occupy an orbital?
A. 1 B. 2 C. 3 D. 4
__A___ 23. Which has the smallest ionization energy?
A. Noble gases B. alkali metals C. halogens D. transition elements
__B___ 24. Metal has a low electro negativity, while nonmetal has
A. The same electro negativity B. high electro negativity
C.low electro negativity D. none of these
__C___ 25. What is true about elements belonging to the same family in the periodic table?
A. They have the same number of nucleons.
B. They have the same electron configuration
C. They have the same valence electron configuration.
D. They have the same number of occupied energy levels.
For Qs 26-30, please select the electron configuration corresponding to the elements from the options given below.
A. 1s2 2s2 2p6 3s2 3p6 4s2
B. 1s2 2s2 2p6 3s2 3p6 4s2 3d5
C. 1s2 2s2 2p6
D. 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p3
__C___ 26. A noble gas
__A___ 27. A metal
_C, D__28. An element belonging to the p-block
__B__ 29. An element belonging to the d-block
__A___30. An element belonging to the s-block
Part II 1. Answer the following questions for an element with an atomic number of 15. You may use the periodic table to
answer these questions.
Phosphorous A. What is the element?
Period 3, Group 15 or VA B. What is the position in the periodic table? Identify its group number and period number.
3 occupied levels C. How many energy levels do electrons in this atom occupy?
5 valence electrons D. How many valence electrons are there in this atom?
3s2 3p3 E. Show the valence electron configuration of this atom.
2. Answer all questions in number 1, for an atom with an atomic number of 24.
A. Chromium
B. Period 4, Group 6 or VIB
C. 4 occupied levels
D. 2 valence electron
E. 4 s2
3. An atom has an atomic mass of 18 and atomic number of 8. What is the number of
A. protons: ___8___
B. electrons: __8__
C. neutrons: __10___
Part III Give the contribution/s of the following scientists: (2 pts each)
1. JJ Thomson- discoverer
2. John Dalton
3. James Chadwick
Part IV Define the following terms:
1. Protons
2. Electrons
3. Neutrons
4. Electron configuration
5. Periodic table
6. Valence electrons
Prepared by:

3. MARIETTA C. GABE
Subject Teacher