140 TExES Chemistry 8 - 12 Exam Practice Questions
1. Science is composed of these areas:
A. Natural Science
B. Social Science
C. Formal Science
D. All of the above
2. Scientific method is used to:
A. Explore predetermined theories
B. Prove that processes follow a predictable path
C. Integrate information
D. All of the above
3. Which step is not part of the scientific method?
A. Question posed
B. Research done
C. Earlier tests are ignored
D. Analysis
4. Chemistry studies matter in relation to:
A. Evolution
B. Entropy
C. The environment
D. All of the above
5. Which of the following is not a discipline in chemistry?
A. Organic
B. Biochemistry
C. Molecular
D. Analytical
6. The fundamental states of matter include:
A. Atoms
B. Plasma
C. Elements
D. All of the above
7. Forms of energy include:
A. Genes
B. Elements
C. Electric
D. All of the above
8. The chemical reaction rate depends on:
A. Reactants involved
B. Unpredictable and impossible to understand
C. Motion of the molecules involved
D. All of the above
9. Types of chemical reactions include:
A. Genetic
B. Synthesis
C. Evolution
D. All of the above
10. Students studying science should be assessed on their ability to:
A. Memorize data
B. Communicate related data
C. Evaluate results
D. All of the above
ANSWER KEY EXAM 140
1. Answer: D
Natural Science is concerned with the natural world. Social Science studies human behavior. Both are based on empirical evidence, which is observable data that can be verified by other scientists working in similar situations under the same conditions. Formal Science is the systematic study of a specific area. It is essential to developing hypotheses, theories and laws used in other scientific disciplines, i.e., describing how things work (natural science) and how people think and why they do what they do individually and as a society (social sciences). It is based on a priori evidence, which proceeds from a theory or assumption rather than observable phenomena. Applied Science is using the results of scientific research in any of the natural, social and formal sciences and adapting it to address human needs.
2. Answer: c
Scientific Method is a set of procedures used to study natural phenomena. It provides guidelines with which to pose questions, analyze data and reach conclusions. It is used to investigate an event, gain knowledge or correct earlier conclusions about the occurrence and integrate the new information with previously learned data. Researchers pose hypotheses and design experiments and studies to test them. The process must be objective, documented and shared with other researchers, so the results can be verified by replicating the study in similar situations under the same conditions. Scientific method rarely follows a predictable path. The testing of one hypothesis usually leads to other questions, which leads to the formation of other hypotheses.
3. Answer: C
The steps described are not necessarily used in exactly the same way in all sciences. Sometimes they happen at the same time or in a different order and may be repeated during the course of the study, but should be applied with intelligence, imagination and creativity. The following sequence is the one used most of the time:
- A question is asked about a natural phenomenon. It should be stated in specific language to focus the inquiry.
- The subject is thoroughly researched. Previous test results are studied. It is important to understand what the earlier experiment(s) proved or disproved.
- With information gleaned from researching the topic, a hypothesis is formed about a cause or effect of the event or its relationship to other occurrences.
- An experiment is designed and conducted to test the hypothesis and gather information.
- The resulting data is analyzed to determine if they support or refute the hypothesis.
4. Answer: B
Chemistry grew out of the practice known as alchemy, a philosophical and spiritual discipline that investigated the possibility of transforming base metals into gold. Modern chemistry is the physical science that studies the composition, structure, properties and reactions of atoms, molecules, crystals and other aggregate matter by themselves or in relationship to each other. It is sometimes called the "central science" because it connects the other natural sciences. Chemistry studies matter in relation to energy (the capacity to do work) and entropy (the measurement of energy unable to do work) and the spontaneity of chemical reactions (the changing of matter into one or more substances).
5. Answer: C
Chemistry is divided into several disciplines based on the type of matter being studied:
- Organic Chemistry studies compounds that contain carbon. Note: Some carbon compounds are considered inorganic compounds.
- Inorganic Chemistry studies mineral compounds.
- Biochemistry studies organisms capable of responding to stimuli, reproduction and growth.
- Physical Chemistry studies energy systems at the macro, molecular and sub-molecular levels.
- Analytical Chemistry studies matter and its chemical composition and structure.
6. Answer: B
Matter is any substance that has mass and takes up space. It is all the physical items in the universe; dirt, air, water, pencils, parsnips and pumpkins. Matter is composed of atoms (small particles with a positively charged core made of protons, neutrons and electrons) and molecules (the smallest part of an element that contains all of its particular properties). Elements have only one atom and cannot be broken down further. One hundred and nine (109) elements have been identified. Elements combine to form compounds, which have a specific ratio of atoms. This determines the structure and defines the chemical properties of the substance. The four fundamental states of matter are:
- Solid: Molecules packed tightly together with a definite shape and volume
- Liquid: Molecules have the ability to move and do not disperse readily
- Gas: Molecules move very quickly, have low density and are distributed uniformly
- Plasma: The substance that contains proteins, fats and other molecules suspended in water; it makes up the living matter of plant and animal cells
7. Answer: C
Energy is the capacity to do work or cause change. It is always associated with movement whether at the molecular, atomic or subatomic level. Its companion is entropy, which is the measurement of energy unable to do work. Energy can change forms; but it cannot be created or destroyed. It is a closed system that remains constant. This Principle of Physics is known as the Conservation of Energy. There are many forms of energy: Light (electromagnetic radiation within a specific wavelength), heat (movement of atoms or molecules), electric (attraction and repulsion of electrons and protons), mechanical (related, produced or dominated by physical force) and nuclear (the charged center of an atom) to name the most common. There are two types of energy: Potential, which is energy that is stored and waiting to be used and kinetic, which is energy that is currently being used.
8. Answer: A
A chemical reaction is a process that changes one substance into another substance, i.e., the product, with an altogether different structure and composition. There is a rearrangement of the bonds (strong electrical force) that hold the atoms together. However, the total mass and number of atoms equals the sum of all the reactants, i.e., the original materials. Energy is always either consumed or liberated. The chemical reaction rate measures the amount of product produced or consumed. It depends on the reactants involved, surface area available for contact, the type of chemical change, the temperature and pressure applied and if and what kind of catalyst is used.
9. Answer: B
All chemical reactions fall into one of the following categories:
- Combustion: Oxygen combines with another compound to form water and carbon dioxide; an exothermic process because heat and light are produced.
- Synthesis: Two or more simple compounds combine and form a more complicated, totally different substance
- Decomposition: A complex compound breaks down into simpler substances, which sometimes disintegrate; the opposite of synthesis
- Single Displacement: One element trades places with another in the same compound
- Double Displacement: The anions (ion with a negative electrical charge) and cations (ion or atom with a positive electrical charge) of different molecules switch places and form two totally different compounds
- Acid-Base: A double displacement occurs when an acid and a base (alkaline substance) react and produce water.
10. Answer: C
The U.S. Department of Education established criteria for testing comprehension of science concepts using recommendations from the National Assessment of Educational Progress. Students are required to not only know facts but also be able to integrate those facts into previously learned information by using critical thinking skills developed through the study of science, i.e., they need to be able to use the facts in practical applications found in the real world. The assessments developed by educators, curriculum specialists and the business community emphasize the importance of assessing students' ability to reason, understand concepts, solve problems, evaluate results and communicate knowledge of the subject matter. The tests attempt to measure whether students can take cognitive skills learned in science, apply them in other disciplines and use them outside of school in meaningful ways.
Last Updated: 02/21/2013