chapter 2 quiz Flashcards
which of the following elements is not one of the four most common elements in living systems
a: nitrogen
b:zinc
c:carbon
d:oxygen
zinc
an atom with a positive charge has ______
a:more protons than electrons
b:more electrons than protons
c:more neutrons than protons
d:more protons than neutrons
more protons than electrons
beryllium’s atomic mass is 9 and its atomic number is 4. how many neutrons are found in a beryllium atom?
a:9
b:2
c:13
d:5
5
isotopes of an element have the same number of _______ and different numbers of ________.
a: protons, neutrons
b:protons, electrons
c:neutrons, protons
d:neutrons, electrons
protons, neutrons
the second electron shell of an atom can hold a maximum of _____electrons
a:1
b:2
c:3
d:8
8
nitrogen has an atomic number of 7; therefore it has_____ electrons in its outermost electron shell
a:1
b:10
c:18
d:5
5
the bond between oppositely charged ions is a ______ bond
a:polar covalent
b:hydrogen
c:ionic
d:isotonic
ionic
what name is given to bonds that involve the sharing of electrons?
a:hydrogen
b:covalent
c:ionic
d:isotonic
covalent
which of these is most closely associated with darwin
a:dna structure
b:cell theory
c:genetic code
d:natural selection
natural selection
water molecules form hydrogen bonds because
a:the water molecule is polar
b:the oxygen molecule is positively charged
c:the water molecule forms a tetrahedron
d: the hydrogen atoms are negatively charged
the water molecule is polar
ironically the world’s oceans throughout the tropics are not very productive (these oceans do not capture much sunlight through the process of photosynthesis). on the other hand some of the most productive oceans are the artic and antartic. what might be limiting production in the tropical oceans?
a:low temperature
b:low sunlight
c:low nutrients
d:high nutrients
low nutrients
the tendency of water molecules to stick together is referred to as
a:adhesion
b:polarity
c:cohesion
d:transpiration
cohesion