Question 1

The reaction 2KBr + F₂ → 2KF + Br₂ is an example of a _____ reaction.

Accepted Answer

This reaction is a single replacement reaction because one element (F) replaces another element (Br) in a compound (KBr), resulting in the formation of a new compound (KF) and a new element (Br).

Question 2

When nitrogen (N₂)reacts with sodium (Na), sodium nitride (Na₃N)is formed. The balanced equation for the reaction would be:

Accepted Answer

The answer of When nitrogen (N₂)reacts with sodium (Na), sodium...

Question 3

The reaction below would be considered _____ . CaCO₃ + heat → CaO + CO₂

Accepted Answer

This reaction involves the breakdown of calcium carbonate (CaCO3) into calcium oxide (CaO) and carbon dioxide (CO2) upon heating, which is a decomposition reaction. Since it requires heat to proceed, it is considered endothermic.

Question 4

Suppose 2.43 g of magnesium is reacted with 3.20 g of oxygen: 2Mg + O₂ → 2MgO. How many grams of MgO will be produced?

Accepted Answer

The answer of Suppose 2.43 g of magnesium is reacted...

Question 5

What is the assigned oxidation number for molybdenum in aluminum molybdate, Al₂(MoO₄)₃?

Accepted Answer

In aluminum molybdate, the formula can be simplified to Al2(MoO4)3. Aluminum (Al) has a +3 oxidation state, and oxygen (O) has a -2 oxidation state. To balance the charges in the compound, molybdenum (Mo) must have a +6 oxidation state.

Question 6

Which of the following conversion factors would allow one to calculate the amount of PbI₂ produced from a given amount of NaI in the following unbalanced reaction? Pb(NO₃)₂ + Nal → Pbl₂ + NaNO₃

Accepted Answer

The answer of Which of the following conversion factors would...

Question 7

Which of the following types of chemical reaction classes always involve oxidation?

Accepted Answer

The answer of Which of the following types of chemical...

Question 8

Automotive car batteries rely on the reaction shown below. Identify the spectator ion(s). PbO₂(s)+ 4 H⁺(aq)+ 2 SO₄^2-(aq)+ Pb(s)→ 2 PbSO₄(s)+ 2 H₂O(l)

Accepted Answer

In this reaction, all ions participate in forming products, so there are no spectator ions.

Question 9

The following would represent what type of chemical reaction?

Accepted Answer

The answer of The following would represent what type of...

Question 10

Tincture of iodine is an antiseptic. Which of the following is another antiseptic?

Accepted Answer

The answer of Tincture of iodine is an antiseptic. Which...

Question 11

The modern definition of oxidation is a process

Accepted Answer

The modern definition of oxidation involves the loss of electrons, not the gain of electrons, reaction with oxygen, or gain of hydrogen. Therefore, none of the provided choices accurately describe the modern definition of oxidation.

Question 12

Tests are to be conducted on new anti-cancer drug and you are to prepare a fresh supply for the human subject studies. You discover that you were able to produce 1.345 g of this substance although it was theoretically possible to make 1.433 g. What was the percent yield for this synthesis?

Accepted Answer

The percent yield is calculated using the formula: (actual yield / theoretical yield) * 100. So, (1.345 g / 1.433 g) * 100 = 93.86%.

Question 13

A percentage yield greater than 100% has been reported in a scientific paper you are assigned to read. What would be a reasonable explanation for this?

Accepted Answer

Small measurement errors can lead to a reported yield greater than 100%, as it might include impurities or inaccuracies in measuring reactants and products.

Question 14

Which is not a meaning of oxidation?

Accepted Answer

Oxidation originally referred to reactions involving the combination of oxygen with other elements but has since expanded to include other types of chemical reactions. Oxidation is correctly defined as losing electrons (D), losing hydrogen (B), or combining with oxygen (C). Gaining electrons (A) is actually the definition of reduction, not oxidation.

Question 15

When the following equation is balanced, how many oxygen atoms are present on the reactant side of the equation? C₂H₆ + O₂ → CO₂ + H₂O

Accepted Answer

The balanced equation is:C2H6 + 7O2 → 2CO2 + 3H2OThere are 14 oxygen atoms on the reactant side of the equation.

Question 16

According to the law of conservation of matter, which of the following may NEVER occur as a result of a chemical reaction?

Accepted Answer

The law of conservation of matter states that matter cannot be created or destroyed in an isolated system. This means that the total mass of the reactants before a chemical reaction must equal the total mass of the products after the reaction, making a reduction in total mass impossible.

Question 17

A percentage yield less than 100% is often obtained in a reaction. What is(are)the reason for obtaining less than theoretically predicted?

Accepted Answer

All of the choices listed are common reasons for obtaining a percentage yield less than 100% in a reaction. Side reactions can consume reactants, poor laboratory technique can lead to loss of product, and incomplete reactions mean not all reactants are converted to the intended product.

Question 18

Consider the following chemical equation. Which substance is oxidized? BaCl₂ (aq)+ H₂SO₄ (aq)→ BaSO₄ (s)+ 2HCl (aq)

Accepted Answer

In this reaction, there is no change in oxidation states of any of the elements involved. It is a double displacement reaction, not a redox reaction.

Question 19

A container is filled with 4.0 g H₂ and 5.0 g O₂. The mixture is ignited to produce water according to the following equation. How much water is produced? 2H₂ + O₂ → 2H₂O

Accepted Answer

The reaction is limited by the amount of O₂. 5.0 g of O₂ is 0.15625 moles, which can react with 0.3125 moles of H₂ (0.625 g). This produces 0.3125 moles of H₂O, which is 5.6 g.

Question 20

What are coefficients needed to balance the following reaction? 2 CH₄ + ____ O₂ → ____ CO₂ + ____ H₂O

Accepted Answer

The coefficients needed to balance the reaction are 2 CH₄ + 4 O₂ → 4 CO₂ + 4 H₂O.

Quiz 5: Chemical Reactions

The reaction 2KBr + F₂ → 2KF + Br₂ is an example of a _____ reaction.

When nitrogen (N₂) reacts with sodium (Na) , sodium nitride (Na₃N) is formed. The balanced equation for the reaction would be:

The reaction below would be considered _____ . CaCO₃ + heat → CaO + CO₂

Suppose 2.43 g of magnesium is reacted with 3.20 g of oxygen: 2Mg + O₂ → 2MgO. How many grams of MgO will be produced?

What is the assigned oxidation number for molybdenum in aluminum molybdate, Al₂(MoO₄) ₃?

Which of the following conversion factors would allow one to calculate the amount of PbI₂ produced from a given amount of NaI in the following unbalanced reaction? Pb(NO₃) ₂ + Nal → Pbl₂ + NaNO₃

Which of the following types of chemical reaction classes always involve oxidation?

Automotive car batteries rely on the reaction shown below. Identify the spectator ion(s) . PbO₂(s) + 4 H⁺(aq) + 2 SO₄^2-(aq) + Pb(s) → 2 PbSO₄(s) + 2 H₂O(l)

The following would represent what type of chemical reaction?

Tincture of iodine is an antiseptic. Which of the following is another antiseptic?

The modern definition of oxidation is a process

Tests are to be conducted on new anti-cancer drug and you are to prepare a fresh supply for the human subject studies. You discover that you were able to produce 1.345 g of this substance although it was theoretically possible to make 1.433 g. What was the percent yield for this synthesis?

A percentage yield greater than 100% has been reported in a scientific paper you are assigned to read. What would be a reasonable explanation for this?

Which is not a meaning of oxidation?

When the following equation is balanced, how many oxygen atoms are present on the reactant side of the equation? C₂H₆ + O₂ → CO₂ + H₂O

According to the law of conservation of matter, which of the following may NEVER occur as a result of a chemical reaction?

A percentage yield less than 100% is often obtained in a reaction. What is(are) the reason for obtaining less than theoretically predicted?

Consider the following chemical equation. Which substance is oxidized? BaCl₂ (aq) + H₂SO₄ (aq) → BaSO₄ (s) + 2HCl (aq)

A container is filled with 4.0 g H₂ and 5.0 g O₂. The mixture is ignited to produce water according to the following equation. How much water is produced? 2H₂ + O₂ → 2H₂O

What are coefficients needed to balance the following reaction? 2 CH₄ + O₂ → CO₂ + H₂O

Quiz 5: Chemical Reactions

The reaction 2KBr + F2 → 2KF + Br2 is an example of a _____ reaction.

When nitrogen (N2) reacts with sodium (Na) , sodium nitride (Na3N) is formed. The balanced equation for the reaction would be:

The reaction below would be considered _____ . CaCO3 + heat → CaO + CO2

Suppose 2.43 g of magnesium is reacted with 3.20 g of oxygen: 2Mg + O2 → 2MgO. How many grams of MgO will be produced?

What is the assigned oxidation number for molybdenum in aluminum molybdate, Al2(MoO4) 3?

Which of the following conversion factors would allow one to calculate the amount of PbI2 produced from a given amount of NaI in the following unbalanced reaction? Pb(NO3) 2 + Nal → Pbl2 + NaNO3

Which of the following types of chemical reaction classes always involve oxidation?

Automotive car batteries rely on the reaction shown below. Identify the spectator ion(s) . PbO2(s) + 4 H+(aq) + 2 SO42-(aq) + Pb(s) → 2 PbSO4(s) + 2 H2O(l)

The following would represent what type of chemical reaction?

Tincture of iodine is an antiseptic. Which of the following is another antiseptic?

The modern definition of oxidation is a process

Tests are to be conducted on new anti-cancer drug and you are to prepare a fresh supply for the human subject studies. You discover that you were able to produce 1.345 g of this substance although it was theoretically possible to make 1.433 g. What was the percent yield for this synthesis?

A percentage yield greater than 100% has been reported in a scientific paper you are assigned to read. What would be a reasonable explanation for this?

Which is not a meaning of oxidation?

When the following equation is balanced, how many oxygen atoms are present on the reactant side of the equation? C2H6 + O2 → CO2 + H2O

According to the law of conservation of matter, which of the following may NEVER occur as a result of a chemical reaction?

A percentage yield less than 100% is often obtained in a reaction. What is(are) the reason for obtaining less than theoretically predicted?

Consider the following chemical equation. Which substance is oxidized? BaCl2 (aq) + H2SO4 (aq) → BaSO4 (s) + 2HCl (aq)

A container is filled with 4.0 g H2 and 5.0 g O2. The mixture is ignited to produce water according to the following equation. How much water is produced? 2H2 + O2 → 2H2O

What are coefficients needed to balance the following reaction? 2 CH4 + ____ O2 → ____ CO2 + ____ H2O

The reaction 2KBr + F₂ → 2KF + Br₂ is an example of a _____ reaction.

When nitrogen (N₂) reacts with sodium (Na) , sodium nitride (Na₃N) is formed. The balanced equation for the reaction would be:

The reaction below would be considered _____ . CaCO₃ + heat → CaO + CO₂

Suppose 2.43 g of magnesium is reacted with 3.20 g of oxygen: 2Mg + O₂ → 2MgO. How many grams of MgO will be produced?

What is the assigned oxidation number for molybdenum in aluminum molybdate, Al₂(MoO₄) ₃?

Which of the following conversion factors would allow one to calculate the amount of PbI₂ produced from a given amount of NaI in the following unbalanced reaction? Pb(NO₃) ₂ + Nal → Pbl₂ + NaNO₃

Automotive car batteries rely on the reaction shown below. Identify the spectator ion(s) . PbO₂(s) + 4 H⁺(aq) + 2 SO₄^2-(aq) + Pb(s) → 2 PbSO₄(s) + 2 H₂O(l)

When the following equation is balanced, how many oxygen atoms are present on the reactant side of the equation? C₂H₆ + O₂ → CO₂ + H₂O

Consider the following chemical equation. Which substance is oxidized? BaCl₂ (aq) + H₂SO₄ (aq) → BaSO₄ (s) + 2HCl (aq)

A container is filled with 4.0 g H₂ and 5.0 g O₂. The mixture is ignited to produce water according to the following equation. How much water is produced? 2H₂ + O₂ → 2H₂O

What are coefficients needed to balance the following reaction? 2 CH₄ + O₂ → CO₂ + H₂O