1.
a.) Which of the following single replacement reactions will result in no reaction?
Correct Answer
B. Ag + CuNO3
2.
b.) Which of the following statements about the single replacement reaction below is TRUE?
Correct Answer
B. Sodium gives electrons to silver, making sodium a cation.
Explanation
In a single replacement reaction, a more reactive element replaces a less reactive element in a compound. In this case, sodium, which is more reactive than silver, gives electrons to silver, causing it to become a cation. This means that sodium loses electrons and becomes a cation. Therefore, the statement "Sodium gives electrons to silver, making sodium a cation" is true.
3.
c.) What precipitate will form from the following double replacement reaction?
Correct Answer
A. AgCl
Explanation
In the given double replacement reaction, AgCl and NaNO3 are the reactants. When these two compounds react, they exchange ions and form AgNa and NaCl. AgCl is insoluble in water, meaning it forms a solid precipitate. Therefore, the precipitate that will form from this reaction is AgCl.
4.
e.) Which of the following solutions will be the strongest electrolyte?
(Note: HCl is a strong acid; HC2H3O2 is a weak acid)
Correct Answer
A. 1 M HCl
Explanation
The strongest electrolyte will be the solution with the highest concentration of ions. HCl is a strong acid, which means it dissociates completely in water to form H+ and Cl- ions. Therefore, a 1 M solution of HCl will have a higher concentration of ions compared to the other solutions, making it the strongest electrolyte. HC2H3O2 is a weak acid, so it does not completely dissociate in water, resulting in a lower concentration of ions in the solution.
5.
d.) What is the net ionic equation for the following double replacement reaction?
Correct Answer
A. Ca2+(aq) + OH-(aq) --> Ca(OH)2 (s)
Explanation
The net ionic equation for the given reaction is Ca2+(aq) + 2OH-(aq) --> Ca(OH)2 (s). This equation represents the reaction between calcium ions and hydroxide ions to form calcium hydroxide as a solid precipitate. The sodium ions and nitrate ions do not participate in the reaction and are spectator ions, so they are not included in the net ionic equation.
6.
f.) Which of the following is an example of an acid?
Correct Answer
A. HNO3
Explanation
HNO3 is an example of an acid because it is a strong acid known as nitric acid. It dissociates completely in water to produce hydrogen ions (H+) and nitrate ions (NO3-). Acids are substances that release hydrogen ions when dissolved in water, and HNO3 fits this definition. NaOH, CuOH, and AgOH are examples of bases because they release hydroxide ions (OH-) when dissolved in water.
7.
a.) What are the products of the following reaction?
Correct Answer
A. Cu + Na2S
Explanation
When copper (Cu) reacts with sodium sulfide (Na2S), the products formed are copper sulfide (CuS) and sodium (Na). This can be represented by the balanced chemical equation: Cu + Na2S -> CuS + 2Na. Therefore, the correct answer is Cu + Na2S.
8.
a.) What are the products of the following reaction?
Correct Answer
D. No reaction will occur
Explanation
The reaction between Au3N and K will not produce any products because there is no evidence of a chemical reaction occurring between the two substances. The presence of Au3N and K alone does not indicate any potential reaction or formation of new compounds. Therefore, the correct answer is that no reaction will occur.
9.
a.) What are the products of the following reaction?
Correct Answer
A. Al2O3 + Fe
Explanation
The correct answer is Al2O3 + Fe. This is because when aluminum oxide (Al2O3) reacts with iron (Fe), it forms aluminum oxide (AlO) and iron oxide (Fe2O3).
10.
a.) What are the products of the following reaction?
Correct Answer
D. No reaction will occur
Explanation
The given reaction involves the combination of magnesium oxide (MgO) with calcium (Ca). However, the products formed from this reaction are not possible based on the given equation. Therefore, no reaction will occur.
11.
b.) Which of the following statements about the single replacement reaction below is TRUE?
Correct Answer
A. Li gives electrons to K, making Li a cation.
Explanation
In a single replacement reaction, a more reactive element replaces a less reactive element in a compound. In this case, Li (lithium) is more reactive than K (potassium), so it gives electrons to K, making Li a cation.
12.
b.) Which of the following statements about the single replacement reaction below is TRUE?
Correct Answer
A. Ca gives electrons to Zn, making Ca a cation.
Explanation
In a single replacement reaction, a more reactive metal can replace a less reactive metal in a compound. In this case, calcium (Ca) is more reactive than zinc (Zn). When Ca gives electrons to Zn, Ca loses electrons and becomes a cation (Ca2+). Zn gains electrons and becomes a neutral atom, not a cation. Therefore, the statement "Ca gives electrons to Zn, making Ca a cation" is true.
13.
b.) Which of the following statements about the single replacement reaction below is TRUE?
Correct Answer
D. Al gives electrons to Fe, making Al a cation.
Explanation
In a single replacement reaction, a more reactive element replaces a less reactive element in a compound. In this reaction, Al (aluminum) is giving electrons to Fe (iron), causing Al to become a cation (positively charged ion) and Fe to become a neutral element. Therefore, the statement "Al gives electrons to Fe, making Al a cation" is true.
14.
b.) Which of the following statements about the single replacement reaction below is TRUE?
Correct Answer
D. K gives electrons to Mg, making K a cation.
Explanation
In a single replacement reaction, one element replaces another element in a compound. The element that is being replaced loses electrons and becomes a cation, while the element that is doing the replacing gains electrons and becomes an anion. In this reaction, K gives electrons to Mg, which means K is losing electrons and becoming a cation. Therefore, the statement "K gives electrons to Mg, making K a cation" is true.
15.
c.) What precipitate will form from the following double replacement reaction?
Correct Answer
A. No precipitate will form.
Explanation
In a double replacement reaction, the cations and anions of two different compounds switch places to form two new compounds. In this case, CaS and KNO3 are the two compounds involved. However, when these compounds react, they do not form a precipitate. This means that no solid substance will be formed and separated from the solution. Therefore, the correct answer is "No precipitate will form."
16.
c.) What precipitate will form from the following double replacement reaction?
Correct Answer
A. No precipitate will form.
Explanation
In a double replacement reaction, the cations and anions of two different compounds switch places. In this case, the reaction is between NaOH and KCl. When NaOH and KCl are mixed, they will dissociate into Na+ and OH- ions, and K+ and Cl- ions respectively. Since none of these ions form an insoluble compound with each other, no precipitate will form. Therefore, the correct answer is that no precipitate will form.
17.
c.) What precipitate will form from the following double replacement reaction?
Correct Answer
A. Ca(OH)2
Explanation
In the given double replacement reaction, Ca(OH)2 and NaNO3 are the reactants. Double replacement reactions involve the exchange of ions between two compounds. Ca(OH)2 is a base and NaNO3 is a salt. When they react, the Ca2+ ions from Ca(OH)2 will combine with the OH- ions from NaNO3 to form Ca(OH)2, which is a precipitate. Therefore, the precipitate that will form from this reaction is Ca(OH)2.
18.
c.) What precipitate will form from the following double replacement reaction?
Correct Answer
A. CaCO3
Explanation
In this double replacement reaction, CaCO3 and KCl are the reactants. When they react, CaCO3 dissociates into Ca2+ and CO3^2- ions, while KCl dissociates into K+ and Cl- ions. The ions then rearrange to form new compounds. However, since CaCO3 is insoluble in water, it will not dissociate completely and will remain as a solid precipitate. Therefore, the precipitate formed from this reaction is CaCO3.
19.
d.) What is the net ionic equation for the following double replacement reaction?
Correct Answer
A. Pb2+(aq) + I-(aq) --> PbI2 (s)
Explanation
The correct answer is the net ionic equation for the double replacement reaction between Pb2+(aq) and I-(aq) is Pb2+(aq) + I-(aq) --> PbI2(s). This equation represents the formation of solid lead iodide (PbI2) from the aqueous Pb2+ and I- ions. The solid precipitate is formed as a result of the exchange of ions between the two solutions.
20.
d.) What is the net ionic equation for the following double replacement reaction?
Correct Answer
D. No reaction occurs
21.
d.) What is the net ionic equation for the following double replacement reaction?
Correct Answer
A. Ag+(aq) + Cl-(aq) --> AgCl (s)
Explanation
The net ionic equation for the given double replacement reaction is Ag+(aq) + Cl-(aq) --> AgCl (s). This is because the silver ion (Ag+) from the first reactant combines with the chloride ion (Cl-) from the second reactant to form solid silver chloride (AgCl). The sodium ion (Na+) and nitrate ion (NO3-) from the second reactant do not participate in the reaction and remain as spectator ions. Therefore, they are not included in the net ionic equation.
22.
d.) What is the net ionic equation for the following double replacement reaction?
Correct Answer
B. Ca2+ (aq) + (CO3)2- (aq) --> CaCO3 (s)
Explanation
The net ionic equation for the given double replacement reaction is Ca2+ (aq) + (CO3)2- (aq) --> CaCO3 (s). This is because the potassium ion (K+) and chloride ion (Cl-) do not react with each other, so they are not included in the net ionic equation. The only ions that react are the calcium ion (Ca2+) and carbonate ion (CO3)2-, which form solid calcium carbonate (CaCO3) as a product.
23.
e.) Which of the following would make a strong base less dangerous to work with?
Correct Answer
C. Either of these options would make the base safer to work with.
Explanation
Diluting the base to a very low concentration or adding an acid to neutralize the base would both make the base safer to work with. Diluting the base reduces its strength, making it less likely to cause harm or damage. Adding an acid to neutralize the base also reduces its reactivity and potential danger. Therefore, either of these options would effectively decrease the risk associated with working with a strong base.
24.
e.) Which of the following would make a strong acid less dangerous to work with?
Correct Answer
C. Either of these options would make the acid safer to work with.
Explanation
Diluting the acid to a very low concentration or adding a base to neutralize the acid would both make the acid safer to work with. Diluting the acid reduces its concentration, which decreases its reactivity and potential for causing harm. Adding a base to neutralize the acid also reduces its acidity, making it less corrosive and dangerous. Therefore, either of these options would effectively decrease the danger associated with working with a strong acid.
25.
e.) Which of the following statements about strong bases is TRUE?
Correct Answer
A. Strong bases remove hydrogen ions from other compounds easily.
Explanation
Strong bases are substances that can easily accept or remove hydrogen ions (protons) from other compounds. This is because strong bases have a high affinity for hydrogen ions and can readily react with them. In contrast, weak bases have a lower affinity for hydrogen ions and are less effective at removing them from other compounds. Therefore, the statement "Strong bases remove hydrogen ions from other compounds easily" is true.
26.
e.) Which of the following statements about strong acids is TRUE?
Correct Answer
A. Strong acids dissociate more easily than weak acids.
Explanation
Strong acids dissociate more easily than weak acids because they completely ionize in water, meaning that all of the acid molecules break apart into ions. In contrast, weak acids only partially ionize in water, so only a fraction of the acid molecules dissociate into ions. This is due to the difference in the strength of the chemical bonds in strong and weak acids. Strong acids have stronger bonds that are more easily broken, leading to complete dissociation. Weak acids have weaker bonds that are less likely to break, resulting in partial dissociation.
27.
f.) Which of the following statements about acid-base reactions is TRUE?
Correct Answer
A. Acids give hydrogen ions to bases.
Explanation
This statement is true because in acid-base reactions, acids donate hydrogen ions (H+) to bases. Acids are proton donors, meaning they release hydrogen ions when dissolved in water. Bases, on the other hand, accept these hydrogen ions, forming water molecules. This transfer of hydrogen ions is what characterizes acid-base reactions.
28.
f.) A chemical spill was found in a laboratory, but none of the scientists knew which bottle had spilled. The scientists put the chemical through several tests and found that the substance reacted with both metals and bases but did not react with acids. What can be concluded about this substance?
Correct Answer
A. The substance is likely an acid.
Explanation
Based on the information given, the substance reacted with metals and bases but did not react with acids. This suggests that the substance has acid properties, as it reacts with metals and bases. Therefore, the correct conclusion is that the substance is likely an acid.
29.
f.) Which of the following is an example of a base?
Correct Answer
B. NaOH
Explanation
NaOH is an example of a base because it is a hydroxide compound. Bases are substances that release hydroxide ions (OH-) in water and have a pH greater than 7. NaOH dissociates in water to form Na+ and OH- ions, making it a strong base.
30.
f.) A chemical spill was found in a laboratory, but none of the scientists knew which bottle had spilled. The scientists put the chemical through several tests and found that the substance reacted with acids but did not react with bases or metals. What can be concluded about this substance?
Correct Answer
B. The substance is likely a base.
Explanation
Based on the information provided, the substance reacted with acids but did not react with bases or metals. This indicates that the substance has acidic properties and is likely a base.