Chapter 2: Chemistry of Living Things Flashcards
Which one of the following is the study of matter and the energy that causes matter to combine, break apart, and recombine in everything living and nonliving?
A) Biology
B) Geology
C) Chemistry
D) Physics
C) Chemistry
Which one of the following characteristics applies to both living organisms and nonliving things?
A) Composed of matter B) Capable of reproduction C) Capably of storing energy for later use D) Capable of growth E) Composed of cells
A) Composed of matter
A mad scientist has ripped apart an atom and collected all the subatomic particles located in the nucleus of the atom. Which one of the following has he collected?
A) Electrons B) Protons C) Protons and neutrons D) Electrons and protons E) Neutrons and electrons
C) Protons and neutrons
Which one of the following statements is TRUE regarding the structure of the atom?
A) The nucleus is composed of equal numbers of positively charged particles and negatively charged particles
B) All electrons are located at the same distance from the nucleus
C) In small elements, such as carbon, electrons have a positive charge; in larger elements such as barium, electrons have a negative charge
D) Most of the mass of an atom is due to its protons and neutrons
E) Neutrons carry a negative charge
D) Most of the mass of an atom is due to its protons and neutrons
Which one of the following statements CORRECTLY describes the relationship between an atom and an element?
A) An element is the fundamental unit of an atom
B) An element is composed of atoms that are joined together by ionic and covalent bonds
C) An atom is composed of different elements that are joined together by ionic and covalent bonds
D) An atom is the smallest unit of an element that demonstrates all of the properties of that element
D) An atom is the smallest unit of an element that demonstrates all of the properties of that element
The total number of protons and neutrons in an atom can best be determined by
A) atomic mass
B) the subscript number following the chemical symbol
C) the atomic number
D) the charge of the atom
E) the chemical symbol
A) atomic mass
Isotope of an element have the same _______, but different _______.
A) number of electron shells; number of protons
B) atomic number; atomic masses
C) number of neutrons; number of protons
D) atomic mass; atomic numbers
E) chemical symbols
B) atomic number; atomic masses
Radioisotopes have a number of uses in science and medicine. These uses include which one of the following?
A) repairing damaged heart tissue
B) dating fossils and treating cancer
C) providing the power supply in heat pacemakers
D) treating asthma and regulating nerve transmission
E) curing diabetes
B) dating fossils and treating cancer
Chlorine has an atomic number of 17 and an atomic mass of 35. Therefore, chlorine has _____ electrons and _____ neutrons.
A) 17;18 B) 18;17 C) 17;35 D) 35;17 E) 18;18
A) 17;18
Which one of the following is true regarding electrons, shells, and energy?
A) Electrons are located in shells around the nucleus.
B) Electrons are attracted to each other because they have the same charge.
C) In order for an electron to move closer to the nucleus it must absorb energy.
D) The innermost electron shell has the most potential energy.
E) As an electron moves to a shell further from the nucleus it loses energy.
A) Electrons are located in shells around the nucleus.
Which one of the following is a molecule?
A) NaCL B) O C) C D) Lead E) N
A) NaCl
An example of potential energy is/ are A) bonds that hold atoms together. B) energy for creating new molecules. C) dancing. D) running a marathon.
A) bonds that hold atoms together
\_\_\_\_\_\_ bonds hold the hydrogens to the oxygen within a water molecule, and \_\_\_\_\_\_ bonds attract one water molecule to other water molecules. A) Ionic; hydrogen B) Hydrogen: ionic C) Hydrogen; covalent D) Covalent; hydrogen E) Ionic; covalent
C) Hydrogen; covalent
Ions in body fluids of human are referred to as
A) electrolytes
B) osmolytes
C) isotopes
D) atoms
A) electrolytes
Which of the following is true regarding water?
A) Each molecule of water consists of two atoms of hydrogen and one atom of oxygen covalently bonded to each other.
B) The oxygen side of the water molecule is partially positive
C) Water is a type of ion
D) Electrons are shared equally between the atoms of water
E) Water molecules are attracted to each other by ionic bonds
A) Each molecule of water consists of two atoms of hydrogen and one atom of oxygen covalently bonded to each other.
Each of the following statements is TRUE regarding hydrogen bonds EXCEPT which one?
A) Hydrogen bonds hold the two strands of DNA together
B) Hydrogen bonds are responsible for the attraction of Na+ to Cl-
C) Hydrogen bonds are responsible for some aspects of the three dimensional structure of proteins
D) Hydrogen bonds form between different water molecules
B) Hydrogen bonds are responsible for the attraction of Na+ to Cl-
Molecules such as water are referred to as _____ because they are electrically neutral overall but still have partially charged regions
A) electrolytes B) polar molecules C) ions D) covalently charged E) isotopes
B) polar molecules
Water is an excellent solvent for biological systems because
A) it can maintain a relatively unstable temperature for chemical reactions to occur
B) compounds with ionic bonds as well as those with polar covalent bonds readily dissolve in water.
C) it is semisolid at body temperature, preventing it from flowing freely through the human body
D) it can rearrange its bonds, forming covalent bonds with other molecules once dissolved
B) compounds with ionic bonds as well as those with polar covalent bonds readily dissolve in water