Answer the following question given this paragraph: 2.3 Chemical Reactions Chemical reactions, in which chemical bonds are broken and formed, require an initial investment of energy. Kinetic energy, the energy of matter in motion, fuels the collisions of atoms, ions, and molecules that are necessary if their old bonds are to break and new ones to form. All molecules store potential energy, which is released when their bonds are broken. Four forms of energy essential to human functioning are: chemical energy, which is stored and released as chemical bonds are formed and broken; mechanical energy, which directly powers physical activity; radiant energy, emitted as waves such as in sunlight; and electrical energy, the power of moving electrons. Chemical reactions begin with reactants and end with products. Synthesis reactions bond reactants together, a process that requires energy, whereas decomposition reactions break the bonds within a reactant and thereby release energy. In exchange reactions, bonds are both broken and formed, and energy is exchanged. The rate at which chemical reactions occur is influenced by several properties of the reactants: temperature, concentration and pressure, and the presence or absence of a catalyst. An enzyme is a catalytic protein that speeds up chemical reactions in the human body. Q: What term is used to describe the energy of matter in motion? Choices: - frictional energy - gravitational energy - emotional energy - kinetic energy A:
kinetic energy
(Question)
Answer the following question given this paragraph: Q: What do you call an incomplete outer shell of an atom? Choices: - helium shell - motile shell - nucleic shell - valence shell A:
(Answer)
valence shell
Ques: Answer the following question given this paragraph: Socket diagram: Pearson Scott Foresman; Joint diagram: Zachary Wilson. Ball and socket joints allow for a wide range of flexibility . Socket diagram: Public Domain; Joint diagram: CC BY-NC 3.0. Q: What kind of joints allow for a wide range of flexibility? Choices: - anchor - pivot - lever - ball and socket A:
Ans: ball and socket
(Q).
Answer the following question given this paragraph: A geologic map shows the different rocks that are exposed at the surface of a region. Rock units are shown in a color identified in a key. On the geologic map of the Grand Canyon, for example, different rock types are shown in different colors. Some people call the Grand Canyon "layer cake geology" because most of the rock units are in layers. Rock units show up on both sides of a stream valley. Q: What are the three main types of rocks? Choices: - limestone , igneous and metamorphic - plutonic, igneous and metmorphic - crystalline , igneous and metamorphic - sedimentary, igneous and metamorphic A:
(A).
sedimentary, igneous and metamorphic
Ques:Answer the following question given this paragraph: Practically all surfaces. Bacteria can live and grow in practically any environment. It is this ability that has made bacteria the most numerous species on the planet. Q: What is the most numerous species on the planet? Choices: - trees - viruses - humans - bacteria A:

Ans:bacteria
Ques: Answer the following question given this paragraph: assigned a unique one-, two-, or three-letter symbol. The names of the elements are listed in the periodic table, along with their symbols, atomic numbers, and atomic masses. The chemistry of each element is determined by its number of protons and electrons. In a neutral atom, the number of electrons equals the number of protons. Q: The chemistry of each element is determined by its number of what? Choices: - nuclei and neutrons - protons and neutrons - electrons and neutrons - protons and electrons A:
Ans:
protons and electrons