Science MidTerm Review (Study.com Chapter 5)
A Magnesium atom is most likely to have what charge as an ion? (Lesson 2)
+2
How many bonds can hydrogen form? (Lesson 8)
1
How many hydrogen atoms would you expect to find in a saturated hydrocarbon with 7 carbon atoms? (Lesson 19)
16
How many valence electrons are in a carbon dioxide (CO2) molecule? (Lesson 8)
16
If a central atom of a molecule only has two electron domains, what is the bond angle associated with the molecule? (Lesson 11)
180o
How many elements of unsaturation does a molecule with this chemical formula have? (C5H8) (Lesson 19)
2
How many bonding domains are needed for a molecule to have a tetrahedral shape? (Lesson 11)
4
How many dots would you put around carbon, a group IVA element? (Lesson 1)
4
How many dots should be around an elemental symbol in a Lewis dot diagram if it has a full octet? (Lesson 7)
8
How many total dots should the diagram for silicon tetrahydride, SiH4 include? (Lesson 7)
8
How do you represent a triple bond in a structural formula? (Lesson 7)
::: or three horizontal lines
What is a binary compound? (Lesson 4)
A compound composed of only two elements.
Which is the best definition of a covalent compound? (Lesson 6)
A compound formed from the sharing of electrons between two or more nonmetal atoms.
What is a macromolecule? (Lesson 18)
A huge molecule made up of smaller subunits called monomers
What is a nonbonding electron domain? (Lesson 11)
A lone pair of electrons
What types of ions generally form an ionic compound? (Lesson 3)
A metal cation and a non-metal anion
What is a polar molecule? (Lesson 13)
A molecule with a slightly positive side and a slightly negative side.
What is the octet rule? (Lesson 1)
A rule that says atoms like to have full valence shells of eight electrons.
What is an anion? (Lesson 2)
An atom that has gained a valence electron and is negatively charged.
What is a valence electron? (Lesson 1)
An electron at the highest occupied energy level of an atom.
How is an organic compound described? (Lesson 20)
Any compound that contains carbon plus another element.
Why do some molecules have resonance? (Lesson 9)
Because electrons are mobile and will move to different positions within a molecule if they can.
Why is a functional group important? (Lesson 20)
Because it is the portion of the organic molecule capable of characteristic reactions.
Why are metals malleable? (Lesson 17)
Because the atoms can move freely without harming the crystal structure.
Why are metals shiny? (Lesson 17)
Because they reflect light photons.
What happens when both of the orbitals in a molecule are in phase, either both positive or both negative, and the electrons in the bonds are at their lowest energy level? (Lesson 16)
Bonding takes place.
What could be changed about this Lewis dot structure for IO- to make it more clear? (Lesson 8)
Change the bond between I and O to a single line.
Which of the following would be good at conducting electricity? (Lesson 17)
Copper
What is an example of a naturally occurring inorganic macromolecule? (Lesson 18)
Diamond
If a polyatomic ionic compound has gained two hydrogen ions, then how does its name begin? (Lesson 4)
Dihydrogen
What is the correct name for N2 O5? (Lesson 6)
Dinitrogen pentoxide
What type of intermolecular force exists between polar molecules? (Lesson 12)
Dipole-dipole
What charge do group IVA atoms have when they become ions? (Lesson 2)
Either +4 or -4, but they don't usually become ions.
In larger atoms, why can outer electrons move more freely? (Lesson 14)
Electrons are filling higher energy shells, which means that they're farther from the nucleus, and are thus less tightly held.
What is NOT an example of an organic macromolecule? (Lesson 18)
Graphite
What does bond order refer to? (Lesson 16)
How many bonds there are between two atoms.
How are metallic bonds different from ionic and covalent bonds? (Lesson 17)
In metallic bonds, electrons are free floating. They are not transferred or shared like in ionic or covalent bonds.
If oxygen with an electronegativity of 3.4 were to share electrons with lithium, electronegativity of 1.0, what kind of bond would form? (Lesson 10)
Ionic
How are ions formed? (Lesson 2)
Ions are formed when neutral atoms gain or lose electrons to become positively or negatively charged.
What is the correct name for Fe(OH)3? (Lesson 4)
Iron (III) hydroxide
Which of the following describes molecules with the same chemical formula but different molecular structures? (Lesson 19)
Isomer
Which of the following statements BEST explains the molecular orbital theory? (Lesson 16)
It describes how the orbital shapes combine when atoms combine into molecules.
What happens when a neutral molecule becomes temporarily dipole? (Lesson 14)
It induces a temporary dipole on a nearby molecule.
Why is it possible for an alkane to contain an element of unsaturation? (Lesson 19)
It is possible for an alkane to be in a ring.
In hybridization, how do you know how many hybrid orbitals are formed? (Lesson 15)
It is the same as the number of orbitals that have combined.
What is the formula for lithium fluoride? (Lesson 5)
LiF
What is the correct name for MgCl2? (Lesson 4)
Magnesium chloride
What is the formula for Magnesium oxide? (Lesson 5)
MgO
Which of the following will most likely have the highest lattice energy? (Lesson 3)
MgO +2, -2 charge
What monomer are carbohydrates made of? (Lesson 18)
Monosaccharides
Which of the following is an example of an ionic compound? (Lesson 3)
NaCl
Identify the atom that is likely to have the highest electronegativity. (Lesson 10)
Non-metal oxygen, atomic number 8
If carbon, electronegativity of 2.6 were to share electrons with sulfur, electronegativity 2.6, what kind of bond would it form? (Lesson 10)
Non-polar covalent
Which organic macromolecule is responsible for transmitting genetic information? (Lesson 18)
Nucleic Acid
Select the general formula for carboxylic acid. (Lesson 20)
RCOOH
What is usually the first step when drawing a Lewis dot structure? (Lesson 8)
Summing the number of valence electrons.
Which of the following is NOT a property of covalent compounds? (Lesson 6)
Superior malleability
What is an intermolecular force? (Lesson 12)
The attractions between molecules
How can you determine the charge of an ion formed by a representative element? (Lesson 5)
The charge of the ion formed is related to the element's group number.
What does the charge on a polyatomic ion mean? (Lesson 8)
The charge on a polyatomic ion is equivalent to the number of electrons the parent molecule must lose or gain to achieve the octet rule.
What do you look at in the periodic table to determine the number of valence electrons possessed by an element? (Lesson 1)
The element's group number.
What is bond energy? (Lesson 16)
The energy needed to break bonds.
Which of the following is true of intermolecular forces? (Lesson 13)
The forces that exist between molecules.
What is hybridization? (Lesson 15)
The mixing of two or more atomic orbitals to form new orbitals that describe the covalent bonding in molecules
What is the electron sea model? (Lesson 17)
The model of metallic bonding where electrons float free in a sea of electrons around metal atoms.
Identify the requirement for a dipole-dipole force to exist. (Lesson 13)
The molecules need to be very close to each other.
Why does hybridization work? (Lesson 15)
The net energy of the molecule is less than that of the atoms in isolation.
When naming a binary compound, what determines the prefix for an element in the compound? (Lesson 6)
The number of atoms of that element in the compound.
What is the first thing you need to know to use the hybridization theory? (Lesson 15)
The number of valence electrons in the participating atoms
What happens in constructive interference? (Lesson 16)
The orbitals add.
Which of the following best describes the octet rule? (Lesson 2)
The outermost energy shell of an atom likes to be full with eight electrons.
Why must we consider a molecule's shape when determining its polarity? (Lesson 12)
The shape reveals more about distribution of charge than the Lewis dot structure.
What does a Lewis dot diagram allow you to show? (Lesson 1)
The valence electrons in an element.
What is a London dispersion force? (Lesson 14)
The weak intermolecular force that results from the motion of electrons that creates temporary dipoles in molecules.
How do Ca2+ and phosphate(PO4)3- combine to make an electrically neutral compound? (Lesson 5)
Three Ca+2 ions combine with Two (PO4) -3 ions
How is an ionic bond formed? (Lesson 3)
Through the transfer of electrons
Why do some ionic compound names have Roman numerals in them? (Lesson 5)
To indicate the charge on the cation.
How do you determine which way the dipole arrow points? (Lesson 12)
Towards the more electronegative atom.
What is the shape of a Boron Trifluoride molecule, BF3? (Lesson 11)
Trigonal planar
When drawing Lewis dot structures, what should you do if you run out of electrons before all atoms are satisfied? (Lesson 9)
Try double or triple bonds.
A sigma bond occurs when _____. (Lesson 15)
Two orbitals directly overlap but there is only one bonding interaction
Which are the outermost electrons of an atom? (Lesson 6)
Valence electrons
In a Lewis dot structure, what do the dots represent? (Lesson 9)
Valence electrons.
Why is water a bent molecule and not linear? (Lesson 11)
Water has four electron domains (two bonding regions and two pairs of unbound electrons) repelling each other, causing the molecule to be bent.
What is the best definition for resonance? (Lesson 9)
When a molecule or polyatomic ion has more than one correct Lewis dot structure.
Which of the following best describes the term dipole moment? (Lesson 12)
When electrons are unevenly distributed within a molecule
How is a covalent bond formed? (Lesson 10)
When electrons between atoms are shared.
What causes a dipole? (Lesson 14)
When the electrons are concentrated more at one end of a molecule, that end is slightly negative, and the other end, where the electrons aren't as concentrated, is slightly positive.
When is a polar covalent bond formed? (Lesson 10)
When the shared pair of electrons is more attracted to one atom than the other.
How are resonance structures for a molecule or polyatomic ion represented? (Lesson 9)
With a double-headed arrow in between each structure.
Hydrogen bonds exist between X and Y. Which combination could be X and Y? (Lesson 13)
X is water, H2 O Y is ammonia, NH3
Intermolecular forces do NOT have effect on _____. (Lesson 13)
acidity
An organic molecule has the general formula ROH, the compound is an _____. (Lesson 20)
alcohol
Organic molecules always contain _____. (Lesson 19)
carbon
If an ionic compound contains a transition metal, Roman numerals are used to determine the _____. (Lesson 4)
charge on the ion
Which of the following is a property of an ionic compound? (Lesson 3)
crystal lattice structure
An organic compound is represented by RX. Identify X. (Lesson 20)
halogen
London dispersion force is the only intermolecular force that works on _____. (Lesson 14)
noble gases and nonpolar molecules