Chemical Reactions
How does an increase in concentration of reactants affect the rate of a chemical reaction according to collision theory?
It increases the reaction rate by raising the frequency of effective collisions.
It lowers the overall energy of the system, thereby decreasing reaction rate.
It has no effect on the reaction rate but increases the activation energy required.
It decreases the reaction rate by reducing the frequency of effective collisions.
Which of the following reactions is most likely to be spontaneous at all temperatures?
N₂(g) + O₂(g) → 2NO(g)
H₂O(s) → H₂O(l)
CaCO₃(s) → CaO(s) + CO₂(g)
2H₂(g) + O₂(g) → 2H₂O(l)
In a synthesis reaction, how many products are typically formed?
One
Four
Two
Three
If the enthalpy change for a reaction is slightly endothermic but it leads to an increase in disorder, under which condition is the reaction most likely to be spontaneous?
At lower temperatures
At higher temperatures
Only at standard conditions
It will never be spontaneous
What is the general result when an alkali metal from group one reacts directly with a halogen from group seventeen?
Salt formation
Acid production
Dissociation into ions
Precipitate formation
In which compound would you expect the bond between atoms to be primarily covalent due to similar electronegativity values?
HCl
Cl2
CaO
KCl
What is the difference between acid-base reactions and oxidation-reduction reactions?
Acid-base transfers protons and oxidation-reduction transfers electrons.
Acid-base transfers pH and oxidation-reduction transfers charge.
Acid-base transfers charge and oxidation-reduction transfers pH.
Acid-base transfers electrons and oxidation-reduction transfers prptons.

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What distinguishes a combustion reaction from a synthesis reaction when magnesium reacts with oxygen to form magnesium oxide?
A combustion reaction involves the release of energy as heat and light, whereas a synthesis reaction forms a more complex compound.
In both reactions, magnesium oxide decomposes into its elements.
A synthesis reaction requires an electric spark, while a combustion reaction does not.
Both reactions produce carbon dioxide as a byproduct.
Which side are the electrons on for an oxidation equation?
The reactant side, since oxidation means gaining electrons.
The product side, since oxidation means losing electrons.
The reactant side, since oxidation means losing electrons.
The product side, since oxidation means gaining electrons.
What is formed when potassium reacts with water?
Potassium chloride and oxygen gas
Potassium permanganate and water vapor
Potassium oxide and hydrogen peroxide
Hydrogen gas and potassium hydroxide