Question 1

What is the oxidation number of the chlorine in the compound, Ba(ClO₂)₂?

Accepted Answer

In the compound Ba(ClO)₂, the oxidation number of oxygen is -2. Since there are two oxygens, their total contribution is -4. Barium (Ba) typically has an oxidation state of +2. To balance the compound, the chlorine must have an oxidation state that results in a neutral compound. Therefore, if Ba is +2 and O₂ is -4 (2 * -2), chlorine must be +3 to balance the equation to zero.

Question 2

What is the oxidation number of the nitrogen in N₂O?

Accepted Answer

In N2O, the oxidation number of nitrogen is +1. This is because the overall charge of the compound is 0, and oxygen typically has an oxidation number of -2. Therefore, for two nitrogen atoms, the oxidation number must be +2 in total, making each nitrogen +1.

Question 3

What is the oxidation number of the chlorine in [ClO₄]^-?

Accepted Answer

In the perchlorate ion, [ClO4]-, chlorine is bonded to four oxygen atoms. Each oxygen has an oxidation number of -2, and the overall charge of the ion is -1. To balance the charges, chlorine must have an oxidation number of +7.

Question 4

What is the oxidation number for the carbon atom in COCl₂?

Accepted Answer

In COCl2, oxygen has an oxidation number of -2, and chlorine has an oxidation number of -1. The sum of oxidation numbers in a neutral compound is zero. Therefore, carbon must have an oxidation number of +4 to balance the -2 from oxygen and -2 from the two chlorines.

Question 5

What is the oxidation number of each oxygen in HNO₃?

Accepted Answer

The answer of What is the oxidation number of each...

Question 6

What is the oxidation number of the cobalt in CoCl₂?

Accepted Answer

In CoCl₂, chloride (Cl) has an oxidation number of -1 and sulfur (S) has an oxidation number of -2. Therefore, the sum of the oxidation numbers for Cl and S is -3. Since the compound is neutral, the sum of the oxidation numbers of all the elements must be zero. Thus, the oxidation number of the cobalt (Co) must be +2 to balance out the -3 from Cl and S.

Question 7

What is the oxidation number of the chromium atom in the compound, BaCr₂O₇?

Accepted Answer

The compound formula indicates that there are four sulfide ions, which have a charge of -2 each for a total charge of -8. The barium ion has a charge of +2, so the total charge must be balanced by the chromium and oxygen ions. Setting up the equation:

2(+2) + x + (-8) + 1(+7) + 2(-1) = 0

where x is the oxidation number of chromium. Simplifying:

x - 1 = 0

x = +1

Therefore, the oxidation number of the chromium atom in the compound is +6 (choice C).

Question 8

What is the oxidation number of the phosphorus in P₄O₁₀?

Accepted Answer

In this compound, oxygen has an oxidation number of -2 and sulfur has an oxidation number of -2. The overall charge of the compound is 0. To find the oxidation number of phosphorus, we can set up the following equation: 
(+1) + x + (-2) + (-1) + (+1) + (-2) + (-1) + (+1) + (+1) + (-2) + (-1) + 0 = 0 
Simplifying this equation, we get: 
x - 5 = 0 
Solving for x, we get: 
x = +5 
Therefore, the oxidation number of phosphorus in this compound is +5.

Question 9

What is the oxidation number of the nitrogen in [NO₃]^-?

Accepted Answer

In [NO₃]^-, the overall charge of the compound is -1. Since there are two sulfur atoms in this compound with an oxidation state of -2 each, the total charge contributed by sulfur atoms is -4. Therefore, the oxidation state of nitrogen can be calculated as follows: Total charge of the compound = sum of oxidation states of all atoms -1 = x (oxidation state of N) + (-4) + (-1) (oxidation state of P) x = +5 Therefore, the oxidation state of nitrogen in [NO₃]^- is +5.

Question 10

What is the oxidation number of the manganese atom in the formula for the compound KMnO₄?

Accepted Answer

The compound KMnO4 is potassium permanganate, where the oxidation state of manganese (Mn) is +7. This is determined by considering the oxidation states of the other elements in the compound: potassium (K) is +1, oxygen (O) is -2 (for a total of -8 for the four oxygen atoms), and the overall charge of the compound is 0. Solving for the oxidation state of Mn gives +7.

Question 11

What is the oxidation number of the silicon in SiBr₄?

Accepted Answer

The oxidation number of bromine is -1 and sulfur is -2. Therefore, the total oxidation number for the compound is:
Si + 2Br + S + 2B + S + 1B = 0
x + 2(-1) + (-2) + 2(3) + (-2) + 4 = 0
Solving for x, we get:
x = +4
Therefore, the oxidation number of silicon is +4. The correct choice is D.

Question 12

What is the oxidation number of the carbon atom in the compound CO?

Accepted Answer

In CO, oxygen has an oxidation state of -2. Since the molecule is neutral, carbon must balance this with a +2 oxidation state to make the overall charge zero.

Question 13

What is the oxidation number of the phosphorus in PCl₃?

Accepted Answer

The oxidation number of phosphorus in PCl₃ is +3 because the sum of the oxidation numbers of all the atoms in a neutral compound must be zero. The oxidation number of chlorine is -1, so the oxidation number of phosphorus must be +3 in order to balance the equation.

Question 14

What is the oxidation number of the calcium in CaO?

Accepted Answer

In CaO, oxygen has an oxidation number of -2 because it almost always has a -2 oxidation number in its compounds. The overall compound is electrically neutral, so the oxidation number of calcium must be +2 to balance out the -2 oxidation number of the oxygen atom.

Question 15

The "super-ion battery" contains K₂FeO₄ as a replacement for MnO₂ in alkaline dry batteries. What is the charge of the iron atom in the compound K₂FeO₄?

Accepted Answer

In K₂FeO₄, potassium (K) has a charge of +1 and oxygen (O) has a charge of -2. The compound is neutral, so the sum of the charges must be zero. With two K atoms and four O atoms, the charge of Fe must be +6 to balance the charges.

Question 16

Consider the Acid-Base neutralization of sulfuric acid with sodium hydroxide. NaOH (aq) + H₂SO₄→What products are formed in this neutralization reaction?

Accepted Answer

When sulfuric acid (H2SO4) reacts with sodium hydroxide (NaOH), they undergo an acid-base neutralization reaction to form sodium sulfate (Na2SO4) and water (H2O). The balanced chemical equation for this reaction is:

H2SO4 + 2 NaOH → Na2SO4 + 2 H2O

Therefore, the products formed in this neutralization reaction are Na2SO4 and H2O. Choice D is the best option that includes these products, as well as the reactants NaOH and H2SO4 written in their correct chemical formulas. Choices A, B, C, and E do not accurately represent the correct products of this reaction.

Question 17

In which of the following compounds is the oxidation number of the nitrogen atom equal to +5?

Accepted Answer

In HNO₃, the oxidation state of nitrogen is +5. This is because hydrogen is +1, each oxygen is -2, and the sum of oxidation states in a neutral compound is zero.

Question 18

What is the oxidation number of the phosphorus in PF₃?

Accepted Answer

The oxidation number of phosphorus in PF₃ is +3. This is because the fluorine atoms have an oxidation number of -1, and there are three fluorine atoms in the molecule. The sum of the oxidation numbers of all the atoms in a molecule must be zero, so the oxidation number of the phosphorus atom must be +3.

Question 19

Complete and balance the following acid-base neutralization reaction. What are the products with their respective coefficients when exact stoichiometric quantities of reactants are mixed? __ HBr (aq) + __ Ca(OH)₂→

Accepted Answer

HBr (hydrogen bromide) and Ca(OH)2 (calcium hydroxide) react to form CaBr2 (calcium bromide) and 2 H2O (water). The balanced equation is:
2 HBr (aq) + Ca(OH)2 (aq) → CaBr2 (aq) + 2 H2O (l) 
Therefore, the best choice is B which shows the products as 1 CaBr2 and 2 H2O.

Question 20

What is the oxidation number of the sulfur in SO₃?

Accepted Answer

The oxidation number of oxygen is -2. Since there are three oxygen atoms in SO3, the total oxidation number of oxygen is -6. The oxidation number of sulfur is +6, since the sum of the oxidation numbers of all the atoms in a molecule must be zero.

Quiz 3: Equations, the Mole, and Chemical Formulas

What is the oxidation number of the chlorine in the compound, Ba(ClO₂) ₂?

What is the oxidation number of the nitrogen in N₂O?

What is the oxidation number of the chlorine in [ClO₄]^-?

What is the oxidation number for the carbon atom in COCl₂?

What is the oxidation number of each oxygen in HNO₃?

What is the oxidation number of the cobalt in CoCl₂?

What is the oxidation number of the chromium atom in the compound, BaCr₂O₇?

What is the oxidation number of the phosphorus in P₄O₁₀?

What is the oxidation number of the nitrogen in [NO₃]^-?

What is the oxidation number of the manganese atom in the formula for the compound KMnO₄?

What is the oxidation number of the silicon in SiBr₄?

What is the oxidation number of the carbon atom in the compound CO?

What is the oxidation number of the phosphorus in PCl₃?

What is the oxidation number of the calcium in CaO?

The "super-ion battery" contains K₂FeO₄ as a replacement for MnO₂ in alkaline dry batteries. What is the charge of the iron atom in the compound K₂FeO₄?

Consider the Acid-Base neutralization of sulfuric acid with sodium hydroxide. NaOH (aq) + H₂SO₄→What products are formed in this neutralization reaction?

In which of the following compounds is the oxidation number of the nitrogen atom equal to +5?

What is the oxidation number of the phosphorus in PF₃?

Complete and balance the following acid-base neutralization reaction. What are the products with their respective coefficients when exact stoichiometric quantities of reactants are mixed? HBr (aq) + Ca(OH) ₂→

What is the oxidation number of the sulfur in SO₃?

Quiz 3: Equations, the Mole, and Chemical Formulas

What is the oxidation number of the chlorine in the compound, Ba(ClO2) 2?

What is the oxidation number of the nitrogen in N2O?

What is the oxidation number of the chlorine in [ClO4] - ?

What is the oxidation number for the carbon atom in COCl2?

What is the oxidation number of each oxygen in HNO3?

What is the oxidation number of the cobalt in CoCl2?

What is the oxidation number of the chromium atom in the compound, BaCr2O7?

What is the oxidation number of the phosphorus in P4O10?

What is the oxidation number of the nitrogen in [NO3] - ?

What is the oxidation number of the manganese atom in the formula for the compound KMnO4?

What is the oxidation number of the silicon in SiBr4?

What is the oxidation number of the carbon atom in the compound CO?

What is the oxidation number of the phosphorus in PCl3?

What is the oxidation number of the calcium in CaO?

The "super-ion battery" contains K2FeO4 as a replacement for MnO2 in alkaline dry batteries. What is the charge of the iron atom in the compound K2FeO4?

Consider the Acid-Base neutralization of sulfuric acid with sodium hydroxide. NaOH (aq) + H2SO4→What products are formed in this neutralization reaction?

In which of the following compounds is the oxidation number of the nitrogen atom equal to +5?

What is the oxidation number of the phosphorus in PF3?

Complete and balance the following acid-base neutralization reaction. What are the products with their respective coefficients when exact stoichiometric quantities of reactants are mixed? __ HBr (aq) + __ Ca(OH) 2→

What is the oxidation number of the sulfur in SO3?

What is the oxidation number of the chlorine in the compound, Ba(ClO₂) ₂?

What is the oxidation number of the nitrogen in N₂O?

What is the oxidation number of the chlorine in [ClO₄]^-?

What is the oxidation number for the carbon atom in COCl₂?

What is the oxidation number of each oxygen in HNO₃?

What is the oxidation number of the cobalt in CoCl₂?

What is the oxidation number of the chromium atom in the compound, BaCr₂O₇?

What is the oxidation number of the phosphorus in P₄O₁₀?

What is the oxidation number of the nitrogen in [NO₃]^-?

What is the oxidation number of the manganese atom in the formula for the compound KMnO₄?

What is the oxidation number of the silicon in SiBr₄?

What is the oxidation number of the phosphorus in PCl₃?

The "super-ion battery" contains K₂FeO₄ as a replacement for MnO₂ in alkaline dry batteries. What is the charge of the iron atom in the compound K₂FeO₄?

Consider the Acid-Base neutralization of sulfuric acid with sodium hydroxide. NaOH (aq) + H₂SO₄→What products are formed in this neutralization reaction?

What is the oxidation number of the phosphorus in PF₃?

Complete and balance the following acid-base neutralization reaction. What are the products with their respective coefficients when exact stoichiometric quantities of reactants are mixed? HBr (aq) + Ca(OH) ₂→

What is the oxidation number of the sulfur in SO₃?