What form of energy is found in the foods that we eat?
Ans: Foods contain chemical energy.
What form of energy is used to trnasmit messages from one part of the body to another?
Electrical energy is the energy used by nerve cells to transmit messages in the body.
What type of energy is available when we are still? When we are exercising?
Potential energy is available when we are still. PE is converted to kinetic energy when we exercise.
What two elements besides H and N mke up trhe bulk of living matter?
Besides hydrogen and nitrogen, carbon and oxygen help to make up the bulk of living matter.
An element has a mass of 207 and has 125 neutrons in its nucleus. How many protons and electrons does it have and where are they located?
This element has 82 protons in its nucleus and 82 electrons in its orbitals (electron cloud).
How do the terms atomic mass and atomic weight differ?
Atomic mass indicates the sum of hte protons and neutrons in a given atom's nucleus. Atomic weight indicates the average mass of all isotopes of a given element.
What is the meaning of the term "molecule"?
A molecule is 2 or more atoms held together by chemical bonds.
Why is sodium chloride (NaCl) considered a compound, but oxygen gas is not?
A compound is formed when two or more different kinds of atoms chemically bond together, as in NaCl. Oxygen gas is 2 oxygen atoms (the same kind of atom) bonded together.
Blood contains a liquid component and living cells. Would it be classified as a compound or a mixture? Why?
Blood is a mixture because its components are not changed by their combination and they can be separated by physical means.
What kinds of bonds form between water molecules?
Hydrogen bonds (linking H of one water molecule to O of another) form between water molecules.
Oxygen and argon are both gases. Oxygen combines readily iwth other elements, but argon does not. what accounts for this difference?
Argon's valence shell is full: )2e )8e )8e. Hence it is nonreactive.
Assume imaginary compound XY has a polar covalent bond. How does it charge distribution differ from that of XX molecules?
Electrons would spend more time in the vicinity of hte more electonegative atom in XY, whereas electrons in XX would orbit both X atoms to an equal extent.
Which reaction type -synthesis, decomposition, or exchange occurs when fats are digested in your small intestine?
Fats are digested in the small intestines by decomposition reactions
Why are many reactions that occur in living systems irreversible for all intents and purposes?
Biochemical reactions in the body tends to be irreversible because (a) one or more of the products is removed from the reaction site or (b) the product is needed more than the reactants, so the cell would not provide energy to reverse the reaction.
What specific name is given to decomposition reactions in which food fuels are broken down for energy?
Decomposition reactions in which food is broken down for energy are oxidation-reduction O-R reactions.