BIO Chapter 2
The mass of a proton or neutron is about 1,800 times greater than the mass of an electron. Therefore, almost all of the mass of an atom is concentrated in the _____
nucleus.
Some orbitals near the nucleus are spherical ________, while others are dumbbell-shaped __________ . Still others, farther away from the nucleus, have other shapes.
(s orbitals) (p orbitals)
Each electron orbital can hold up to ___ electrons.
2
Each orbital can contain a maximum of ___ electrons.
2
The electrons of oxygen are located in ___ different energy levels. The first energy level consists of one orbital and the second energy level consists of ___ orbitals
2, 4
Which of the following properties of water is not a consequence of its ability to form H bonds? a. Cohesion b. High specific heat c. Adhesion d. Ability to function as a solvent e. Neutral pH
e
Hydrogen bonding between water molecules makes them tend to stick together, how does this affect the specific heat (SH) and heat of vaporization (HOV) of water? a. The SH and HOV of water are high b. The SH and HOV of water are low c. SH is high but HOV is low d. HOV is high but SH is low e. None of these answers are correct
a
What kind of chemical bonds are formed when atoms share one or more pair of electrons? a. Covalent bonds b. Ionic bonds c. Hydrogen bonds d. Polar bonds
a
A polar covalent bond is created when ______
atoms within the bond do not have the same pull on the shared electron, and as a result the electron spends more time around one atom relative to the other atom within the bond.
18O has an atomic number of 8. How many neutrons does 18O have? a. 8 b. 10 c. 12 d. 18
b
Carbon's atomic number is 6. How many electrons are in carbon's outer shell? a. 2 b. 4 c. 6 d. 8
b
If a molecule gains an electron it has been - a. Oxidized b. Reduced c. Electrified d. Deprotonated
b
Paleontologists distinguish rocks from dinosaur bones by touching their tongues to the object. If their tongue sticks, it is considered bone. This occurs because the water from the tongue moves up the porous spaces of bone. What property of water is allowing this to occur? a. Cohesion b. Capillary action c. Water ionization d. Heat of vaporization
b
Typically an increase in temperature causes a rate of a chemical reaction to - a. Decrease b. Increase c. Remain the same
b
An atom with more protons than electrons is - a. An element b. An isotope c. A cation d. An anion
c
Isotopes are atoms of the same element but differ in the number of? a. Electrons b. Protons c. Neutrons d. Orbitals e. Bonds
c
What property of an atom determines how it forms bonds? a. Atomic Mass b. Atomic number c. Valance electrons d. Orbits e. Neutrons
c
Which of the following types of chemical bonds is the strongest? a. Hydrogen Bond b. Ionic Bond c. Covalent Bond e. All are equal strength
c
Which subatomic particle has a positive charge? a.Electron b. Neutron c. Proton d. Neutrino e. Photon
c
A water strider is an insect that can walk on water. How is this possible? a. Capillary action b. Hydration shells c. Hydrophobic exclusion d. Surface tension
d
In the formation of salt, the sodium atom - a. Loses an electron to chlorine b. Becomes a positive ion c. Has one more proton than electron d. A and B are correct e. A, B and C are correct
e
Magnesium chloride is a salt formed from ionic bonds between one magnesium ion and two chloride ions. Magnesium atoms has two electrons in their outer (third) shell and chlorine atoms have seven electrons in their outer shell. How many electrons would be in the outer shell of magnesium once it becomes a ion? a. 1 b. 2 c. 4 d. 6 e. 8
e
Radioactive isotopes - a. Are unstable b. Decay over time c. Emit radiation d. May occur naturally e. All of the above
e
Which of the following has the lowest concentration of H+ ions? a. pH = 2 b. pH = 6 c. pH = 8 d. pH = 12 e. pH = 14
e
The energy levels of electrons are often depicted as well-defined circular orbits called _________ shells for ease of illustration, but this depiction is not accurate.
electron
The larger oxygen atom, with more protons, is more ___________ than the hydrogen atom and attracts the electron pair closer.
electronegative
The chemical behavior of an atom depends primarily on the number and distribution of its __________
electrons.
The orbitals of an atom contain negatively charged particles called ___________
electrons.
Substances composed of atoms that all have the same number of protons are called
elements.
Electrons occupy different ______ levels depending on how far away from the nucleus they are.
energy
Water has a high heat of vaporization, meaning it requires a large amount of ______ to break the hydrogen bonds between water molecules allowing for evaporation.
heat
The bonding of water molecules to each other with weak bonds is called _______ bonding.
hydrogen
Most _____ have one proton and no neutrons.
hydrogen atoms
When water breaks apart, is releases positively charged _________ ions and negatively charged ________ ions.
hydrogen, hydroxide
Due to the electronegative nature of water, ________ atoms in one molecule are attracted to _____________ atoms in other water molecules.
hydrogen, oxygen
Atoms that have gained or lost electrons and are no longer electrically neutral are called
ions.
If different atoms have the same number of protons but different numbers of neutrons they are called
isotopes.
Water is a ______ at room temperature.
liquid
If the nucleus of an atom were the size of a golf ball, the orbit of the nearest electron would be a _______ away.
mile
Water dissociates into an equal number of hydrogen and hydroxide ions, which creates a _______ pH value.
neutral
In a ____________atom, the number of electrons is equal to the number of protons.
neutral atom
Electrons actually are found in complex three-dimensional spaces called ______, and each electron energy level or electron shell contains a specific number of them.
orbitals
The unequal sharing of electrons in a covalent bond creates a(n) __________bond.
polar covalent
The nucleus of an atom always contains one or more _________
protons.
The atomic number of carbon-13 is
six.
Water has a high capacity to_______due to this bonding, meaning water can absorb heat without changing temperature drastically.
store heat
In humans, heat created by our metabolic activities is dispelled as ________ evaporates from our skin.
sweat
The atomic mass of carbon-13 is
thirteen.
Many hydrogen bonds link water molecules together.
true
Scientists can only determine the probability that an electron is at any given location.
true
The attraction between the hydrogen and oxygen atoms in a water compound is ___________.
unequal
Atoms with _______ electron orbitals tend to be more reactive.
unfilled
A molecule of ______ is comprised of one oxygen atom and two hydrogen atoms.
water
