Question 1

All of the following are reactions commonly associated with water except:

Accepted Answer

Fluorine reacts with water to form oxygen gas and hydrogen fluoride, not hypofluorous acid (HOF).

Question 2

What are the allotropes of oxygen?

Accepted Answer

Oxygen has two main allotropes: dioxygen (O₂) and ozone (O₃).

Question 3

Indicate the coefficient in front of H₂O₂ when the following redox equation is balanced in an acidic medium. H₂O₂(aq)+ Cl^-(aq)→ H₂O(l)+ Cl₂(aq)

Accepted Answer

In an acidic medium, the balanced equation is:H₂O₂(aq) + 2Cl^-(aq) + 2H⁺(aq) → 2H₂O(l) + Cl₂(aq)Therefore, the coefficient in front of H₂O₂ is 1.

Question 4

A binary compound that forms when potassium reacts with oxygen has the composition 54.99% K and 45.01% O.This compound contains

Accepted Answer

The given percentages of K and O in the compound suggest that the compound has the formula K2O2. This indicates the presence of superoxide ions, which contain the O2^- unit. So, option C, which has one superoxide ion and one potassium ion, is the best choice. Option A is incorrect because it suggests the presence of only one oxygen atom. Option B is incorrect because the compound has a 1:2 ratio of K and O, which is not possible for peroxide ions. Option D is incorrect because if the compound contained two oxide ions, its formula would be K2O, not K2O2.

Question 5

What are the three major chemicals that are commercially obtained from sea water?

Accepted Answer

Sodium chloride (common table salt), magnesium, and bromine are the three major chemicals that are commercially obtained from sea water. Calcium carbonate and sodium sulfate are also present in sea water, but they are not as commercially significant as the three options listed in answer choice A. Sodium bromide and sodium carbonate are not major chemicals obtained from sea water. Calcium chloride is obtained from other sources, not sea water.

Question 6

Write a balanced net ionic equation for the reaction of potassium with water.

Accepted Answer

Potassium reacts with water to form potassium ions, hydroxide ions, and hydrogen gas.

Question 7

What is not a characteristic of ozone,O₃?

Accepted Answer

Ozone has two single bonds and one double bond, not one single bond and one double bond.

Question 8

Indicate the order of reactivity of the halogens (F₂,Cl₂,Br₂,I₂)with water (fastest to slowest).

Accepted Answer

The order of reactivity of halogens with water is based on their ability to oxidize water to form hypohalous acids, HXO. Fluorine being the most electronegative, has the highest oxidizing power, followed by chlorine, bromine, and iodine. Hence, the correct order of reactivity is F₂ > Cl₂ > Br₂ > I₂.

Question 9

In which of the following reactions does hydrogen peroxide act as a reducing agent?

Accepted Answer

The answer of In which of the following reactions does...

Question 10

How many milliliters of ozone gas at at 25.0°C and 1.00 atm pressure are needed to react with 45.00 mL of a 0.100 M aqueous solution of KI according to the chemical equation shown below? O₃(g)+ 2 I^-(aq)+ H₂O(l)→ O₂(g)+ I₂(s)+ 2 OH^-(aq)

Accepted Answer

The reaction requires 1 mole of O3 for every 2 moles of I-. The moles of I- in 45.00 mL of 0.100 M KI is 0.0045 moles. Therefore, 0.00225 moles of O3 are needed. Using the ideal gas law at 25°C and 1 atm, this corresponds to 55.0 mL of O3 gas.

Question 11

What are the four major ionic constituents of seawater?

Accepted Answer

The four major ionic constituents of seawater are Chloride (Cl-), Sodium (Na+), Sulfate (SO42-), and Magnesium (Mg2+). Option B has all four of these ions listed, whereas the other options have either incorrect or incomplete constituents.

Question 12

In the reaction of ozone shown below,which of the following unbalanced half-reactions shows the species undergoing reduction and the reduced product? O₃(g)+ 2 I^-(aq)+ H₂O(l)→ O₂(g)+ I₂(s)+ 2 OH^-(aq)

Accepted Answer

The answer of In the reaction of ozone shown below,which...

Question 13

What is not a characteristic of the aqueous chemical reactions of hydrogen peroxide?

Accepted Answer

Hydrogen peroxide behaves as a weak acid, not a weak base, in its aqueous chemical reactions. Therefore, choice C is not a characteristic of the aqueous chemical reactions of hydrogen peroxide. Choices A, B, and D are characteristics of the aqueous chemical reactions of hydrogen peroxide.

Question 14

Indicate the coefficient in front of H₂O₂ when the following redox equation is balanced in an acidic medium. H₂O₂(aq)+ MnO₄^-(aq)→ O₂(g)+ Mn²⁺(aq)

Accepted Answer

The answer of Indicate the coefficient in front of H₂O₂...

Question 15

Water accounts for approximately two-thirds of the mass of the adult human body.If an adult human has a mass of 145 pounds,how many water molecules are there in the adult human's body?

Accepted Answer

To find the number of water molecules in an adult human's body, we need to first find the mass of water in the body. Since water accounts for two-thirds of the mass of the body, we can calculate the mass of water as follows:

Mass of water = 2/3 x 145 pounds = 96.7 pounds

Next, we need to convert the mass of water into the number of water molecules. We can use the following conversion factors:

1 mole of water = 18 grams of water = 6.022 x 10^23 water molecules

Using these conversion factors, we can calculate the number of water molecules as follows:

Number of water molecules = (96.7 pounds / 2.205 pounds per kilogram) x (1 kilogram / 1000 grams) x (1 mole / 18 grams) x (6.022 x 10^23 water molecules per mole)

Simplifying this expression, we get:

Number of water molecules = 4.7 x 10^27

Therefore, the best choice is C, which gives the answer as 1.47 x 10^28 molecules (note that this is a typo in the answer choices, and it should be 1.47 instead of 2.43).

Question 16

Write a balanced net ionic equation for the reaction of bromine with water.

Accepted Answer

The reaction of bromine with water forms hypobromous acid (HOBr), hydrogen ions (H⁺), and bromide ions (Br⁻).

Question 17

Which of the following chemical reagents is not used in the purification of water?

Accepted Answer

NaNO₃ (sodium nitrate) is not typically used in the purification of water. The other options listed (Cl₂, CaO, and Al₂(SO₄)₃) are commonly used in water treatment processes.

Question 18

In which compound does oxygen have a -1 oxidation state?

Accepted Answer

The answer of In which compound does oxygen have a...

Question 19

A binary compound that forms when potassium reacts with oxygen has the composition 58.96% Na and 41.04% O.What is the formula of one formula unit of this compound?

Accepted Answer

The answer of A binary compound that forms when potassium...

Question 20

An estimated 1.35 × 10¹⁸ m³ of water is present in the earth's oceans.Assuming water has a density of 1 g/mL then how many kilograms of water does this volume contain?

Accepted Answer

The volume of water is 1.35 × 10^18 m^3. Since 1 m^3 = 10^6 mL and the density of water is 1 g/mL, the mass is 1.35 × 10^18 m^3 × 10^6 mL/m^3 × 1 g/mL = 1.35 × 10^24 g. Converting to kilograms, 1.35 × 10^24 g = 1.35 × 10^21 kg.

Quiz 18: Hydrogen, oxygen, and Water

All of the following are reactions commonly associated with water except:

What are the allotropes of oxygen?

Indicate the coefficient in front of H₂O₂ when the following redox equation is balanced in an acidic medium. H₂O₂(aq) + Cl^-(aq) → H₂O(l) + Cl₂(aq)

A binary compound that forms when potassium reacts with oxygen has the composition 54.99% K and 45.01% O.This compound contains

What are the three major chemicals that are commercially obtained from sea water?

Write a balanced net ionic equation for the reaction of potassium with water.

What is not a characteristic of ozone,O₃?

Indicate the order of reactivity of the halogens (F₂,Cl₂,Br₂,I₂) with water (fastest to slowest) .

In which of the following reactions does hydrogen peroxide act as a reducing agent?

How many milliliters of ozone gas at at 25.0°C and 1.00 atm pressure are needed to react with 45.00 mL of a 0.100 M aqueous solution of KI according to the chemical equation shown below? O₃(g) + 2 I^-(aq) + H₂O(l) → O₂(g) + I₂(s) + 2 OH^-(aq)

What are the four major ionic constituents of seawater?

In the reaction of ozone shown below,which of the following unbalanced half-reactions shows the species undergoing reduction and the reduced product? O₃(g) + 2 I^-(aq) + H₂O(l) → O₂(g) + I₂(s) + 2 OH^-(aq)

What is not a characteristic of the aqueous chemical reactions of hydrogen peroxide?

Indicate the coefficient in front of H₂O₂ when the following redox equation is balanced in an acidic medium. H₂O₂(aq) + MnO₄^-(aq) → O₂(g) + Mn²⁺(aq)

Water accounts for approximately two-thirds of the mass of the adult human body.If an adult human has a mass of 145 pounds,how many water molecules are there in the adult human's body?

Write a balanced net ionic equation for the reaction of bromine with water.

Which of the following chemical reagents is not used in the purification of water?

In which compound does oxygen have a -1 oxidation state?

A binary compound that forms when potassium reacts with oxygen has the composition 58.96% Na and 41.04% O.What is the formula of one formula unit of this compound?

An estimated 1.35 × 10¹⁸ m³ of water is present in the earth's oceans.Assuming water has a density of 1 g/mL then how many kilograms of water does this volume contain?

Quiz 18: Hydrogen, oxygen, and Water

All of the following are reactions commonly associated with water except:

What are the allotropes of oxygen?

Indicate the coefficient in front of H2O2 when the following redox equation is balanced in an acidic medium. H2O2(aq) + Cl-(aq) → H2O(l) + Cl2(aq)

A binary compound that forms when potassium reacts with oxygen has the composition 54.99% K and 45.01% O.This compound contains

What are the three major chemicals that are commercially obtained from sea water?

Write a balanced net ionic equation for the reaction of potassium with water.

What is not a characteristic of ozone,O3?

Indicate the order of reactivity of the halogens (F2,Cl2,Br2,I2) with water (fastest to slowest) .

In which of the following reactions does hydrogen peroxide act as a reducing agent?

How many milliliters of ozone gas at at 25.0°C and 1.00 atm pressure are needed to react with 45.00 mL of a 0.100 M aqueous solution of KI according to the chemical equation shown below? O3(g) + 2 I-(aq) + H2O(l) → O2(g) + I2(s) + 2 OH-(aq)

What are the four major ionic constituents of seawater?

In the reaction of ozone shown below,which of the following unbalanced half-reactions shows the species undergoing reduction and the reduced product? O3(g) + 2 I-(aq) + H2O(l) → O2(g) + I2(s) + 2 OH-(aq)

What is not a characteristic of the aqueous chemical reactions of hydrogen peroxide?

Indicate the coefficient in front of H2O2 when the following redox equation is balanced in an acidic medium. H2O2(aq) + MnO4-(aq) → O2(g) + Mn2+(aq)

Water accounts for approximately two-thirds of the mass of the adult human body.If an adult human has a mass of 145 pounds,how many water molecules are there in the adult human's body?

Write a balanced net ionic equation for the reaction of bromine with water.

Which of the following chemical reagents is not used in the purification of water?

In which compound does oxygen have a -1 oxidation state?

A binary compound that forms when potassium reacts with oxygen has the composition 58.96% Na and 41.04% O.What is the formula of one formula unit of this compound?

An estimated 1.35 × 1018 m3 of water is present in the earth's oceans.Assuming water has a density of 1 g/mL then how many kilograms of water does this volume contain?

Indicate the coefficient in front of H₂O₂ when the following redox equation is balanced in an acidic medium. H₂O₂(aq) + Cl^-(aq) → H₂O(l) + Cl₂(aq)

What is not a characteristic of ozone,O₃?

Indicate the order of reactivity of the halogens (F₂,Cl₂,Br₂,I₂) with water (fastest to slowest) .

How many milliliters of ozone gas at at 25.0°C and 1.00 atm pressure are needed to react with 45.00 mL of a 0.100 M aqueous solution of KI according to the chemical equation shown below? O₃(g) + 2 I^-(aq) + H₂O(l) → O₂(g) + I₂(s) + 2 OH^-(aq)

In the reaction of ozone shown below,which of the following unbalanced half-reactions shows the species undergoing reduction and the reduced product? O₃(g) + 2 I^-(aq) + H₂O(l) → O₂(g) + I₂(s) + 2 OH^-(aq)

Indicate the coefficient in front of H₂O₂ when the following redox equation is balanced in an acidic medium. H₂O₂(aq) + MnO₄^-(aq) → O₂(g) + Mn²⁺(aq)

An estimated 1.35 × 10¹⁸ m³ of water is present in the earth's oceans.Assuming water has a density of 1 g/mL then how many kilograms of water does this volume contain?