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Biology Ch 3. Mouse Mischief. The way in which elements bond to form compounds depends on which of the following?. the size of the electrons. the shape of the nucleus. the number of neutrons in each atom. the electrons in the atoms of the elements.
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Biology Ch 3 Mouse Mischief
The way in which elements bond to form compounds depends on which of the following? the size of the electrons the shape of the nucleus the number of neutrons in each atom the electrons in the atoms of the elements
In what type of bond are electrons shared? ionic nuclear covalent hydrogen
What weak bond holds together the two strands of nucleotides in a DNA molecule? ionic nuclear covalent hydrogen
When an unknown substance is dissolved in water, hydronium ions form. What can you conclude about the substance? The substance is a gas The substance is a bas The substance is an acid The substance is a carbohydrate
Activation energy is needed only by chemical reactions that release energy
In an atom, the number of protons is equal to the number of electrons.
Polar substances dissolve well in water because water also is polar
Most of the chemical reactions in the body would not occur without enzymes
Atoms do not contain protons. electrons. ions.
The attraction between water molecules is caused by covalent bond hydrogen bonds ionic and covalent bonds
An atom is called an ion when it has either lost or gained electrons lost its nucleus more neutrons than protons
The ability of water to form drops is an example of adhesion. cohesion. ionic bonding
One solution has a pH of 2, and another has a pH of 7. Which of the following is true? Both solutions are acidic The solution with a pH of 2 is basic, and the solution with a pH of 7 is acidic. The solution with a pH of 2 is acidic, and the solution with a pH of 7 is neutral.
Plants store the sun’s energy for future use as DNA starch. protein.
Enzymes are usually proteins. decrease the speed of chemical reactions. increase the activation energy of chemical reactions
The smallest unit of matter that cannot be broken down by chemical means is a(n) element. atom. molecule. electron.
The bonds between the atoms that make up water molecules are called covalent bond hydrogen bonds ionic and covalent bond covalent and hydrogen bonds.
An atom is called an ion when it ha either lost or gained electrons. either lost or gained protons. more neutrons than protons lost its nucleus.
A solution is a mixture of polar and nonpolarsubstances protons and neutrons. unevenly distributed substances. evenly distributed substances.
Water is _______ , therefore _______ substances dissolve in it. polar, nonpolar polar, polar nonpolar, nonpolar nonpolar, polar
In a chemical reaction, energy may be absorbed. released. required. All of the above
Without energy, organisms could not maintain homeostasis. carry out chemical reactions. make their own food. All of the above
The basic units of most biomoleculescontain nitrogen. oxygen carbon. amino acids
Compounds are formed when atoms of an element lose an electron. atoms of an element gain an electron atoms of the same element join together. atoms of two different elements join together.
Enzymes are usually carbohydrates. can only catalyze a reaction onc reduce the activation energy of chemical reactions eliminate the activation energy of chemical reactions.
In an atom with the same number of electrons and protons, the electrical charge is neutral. positive. negative. impossible to determine.
Activation energy is needed by chemical reactions that release energy absorb energy. are catalyzed by enzymes. All of the above
The ability of water to form drops is an example of a chemical change. cohesion. adhesion ionic bonding
What kind of bonds do water molecules form with one another? covalent hydrogen ionic Both (a) and (c)
Starch is made of a sugar, a base, and a phosphate group does not contain carbon atoms. is made of amino acids is a carbohydrate in which energy is stored
Two solutions, A and B, are tested for pH. Solution A indicates a pH of 2. Solution B indicates a pH of 7. You conclude that both solutions are acidic. solution A is basic; solution B is neutral. None of the above solution A is acidic; solution B is neutral
An element is defined as a pure substance because it is made of only one kind of compound. molecule. atom. ion.
Atoms bond with other atoms to form compounds because electrons are attracted to each other bonding helps atoms become more stable. bonding makes an element more pure. the nuclei of atoms are attracted to each other.
When food molecules are broken down inside cells, some of the energy in the molecules is stored temporarily in proteins. RNA. DNA. ATP.
Enzymes that take part in a chemical reaction are not considered to be reactants because they do not take part in the reaction. are not changed by the reaction. have no valence electrons. are used up in the reaction