#1
Which type of bond is formed by the sharing of electrons between atoms?
Covalent bond
ExplanationSharing of electrons between atoms.
#2
Which of the following is a characteristic of ionic compounds?
b and c
ExplanationHigh melting and boiling points, conduct electricity when dissolved or melted.
#3
In a chemical reaction, the Law of Conservation of Mass states:
Mass can neither be created nor destroyed
ExplanationTotal mass of reactants equals total mass of products.
#4
Which molecule is known as the 'universal solvent'?
Water
ExplanationWater can dissolve a variety of substances.
#5
Which of the following compounds is an example of a nonpolar molecule?
CO2
ExplanationSymmetrical distribution of electrons.
#6
What type of bond involves the attraction between a cation and an anion?
Ionic bond
ExplanationAttraction between oppositely charged ions.
#7
What is the name of the rule that says atoms tend to combine in such a way that they each have eight electrons in their valence shell?
Octet rule
ExplanationAtoms tend to combine to have eight electrons in their valence shell.
#8
What type of reaction involves one element taking the place of another element in a compound?
Single displacement reaction
ExplanationOne element displaces another from a compound.
#9
What is the term for a substance that speeds up a chemical reaction without being consumed in the process?
Catalyst
ExplanationSpeeds up chemical reactions without being consumed.
#10
Which of the following is a characteristic of a redox reaction?
Change in oxidation states
ExplanationInvolves changes in oxidation numbers.
#11
What is the molecular geometry of a molecule with a tetrahedral electron domain geometry and no lone pairs?
Tetrahedral
ExplanationArrangement of atoms in a tetrahedral shape.
#12
Which principle or rule is used to predict the shape of molecules?
VSEPR theory
ExplanationPredicts molecular geometry based on electron pairs.
#13
In a Lewis structure, what does a dashed line represent?
A partial bond or a resonance structure
ExplanationRepresents a partial bond or resonance structure.