Chemistry SLO Review

Which of these phrases best describes atoms?

• two or more combined elements

• the smallest units of an element

• particles inside a nucleus

• different forms of an element

Which of the following best describes Thomson’s contribution to the atomic theory?

• Electrons exhibit both particle and wavelike behavior.

• Electrons exert repulsive forces on one another.

• Electrons and equal numbers of positive charges exist.

• Electrons absorb discrete amounts of energy.

Which statement explains why MOST of the mass of an atom is contained in the relatively small nucleus?

• Atoms are composed of less dense subunits than the nucleus.

• Protons and neutrons have more mass than electrons.

• The nucleus is located at the center of an atom.

• Atoms are composed of mostly empty space.

Flame tests can be used to identify an element. Each element emits characteristic waves of light when it is heated in a flame. What describes how the light is produced?

• Protons in the ground state lose energy and give off light.

• Protons in the ground state gain energy and are emitted from the nucleus, giving off light.

• Electrons in the ground state lose energy and move to an excited state, giving off light.

• Electrons in the ground state gain energy, move to an excited state, and give off light when they return to the ground state.

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How many electrons are in the outermost energy level of a neutral carbon atom?

• 2

• 4

• 6

• 8

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Which of these elements has the greatest atomic radius?

• H

• N

• Cl

• Cs

Electronegativity is a measure of how easy it is for an atom to attract another electron. The elements He, Ne, and Ar have the lowest electronegativity values. What do these elements have in common?

• They have an outer orbital full of electrons.

• They have one electron in their outer orbital.

• They lose a proton which makes them negatively charged.

• They have an extra electron which makes them positively charged.

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The process of digestion breaks down proteins into smaller molecules that are used to rebuild other proteins. During digestion, proteins undergo

• cell division.

• nuclear reactions.

• natural selection.

• chemical changes.

Which event is an example of a chemical change?

• fog rising off a river

• wood burning in a fireplace

• ice cream melting in the sunshine

• grinding peppercorn into pepper flakes

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Chemical change can be identified by specific observations. Which would most likely indicate a chemical change?

• Solid carbon dioxide changes directly into carbon dioxide gas.

• Rock is slowly worn away by the action of wind and sand.

• A mineral is crushed into fine dust and mixed with water.

• A light green powder forms on the outside of a penny.

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