Question 1

Which is not an isotope of hydrogen?
A)hydrogen-1
B)hydrogen-2
C)hydrogen-3
D)hydrogen-4

Accepted Answer

Hydrogen-4 does not exist as a stable isotope of hydrogen. The three isotopes of hydrogen that do exist are hydrogen-1 (protium), hydrogen-2 (deuterium), and hydrogen-3 (tritium).

Question 2

What is the total volume of the mixture of hydrogen gas and oxygen gas can be obtained from the electrolysis of 90.0 grams of water at 25.0°C and 1.00 atm pressure according to the chemical equation shown below? 2 H₂O(l) 2 H₂(g)+ O₂(g) A)61.1 L B)122 L C)183 L D)366 L

Accepted Answer

First we need to find the moles of water:
n(H2O) = 90.0 g / 18.015 g/mol = 4.994 moles
Then we can use the stoichiometry of the reaction to find the moles of hydrogen gas produced:
n(H2) = 2 × n(H2O) = 9.988 moles
Using the ideal gas law, we can find the volume of the hydrogen gas at the given conditions:
V(H2) = (n(H2) × R × T) / P
V(H2) = (9.988 mol × 0.08206 L·atm/(mol·K) × 298.15 K) / 1.00 atm = 243.9 L
Similarly, we can find the moles of oxygen gas produced:
n(O2) = 1 × n(H2O) = 4.994 moles
And the volume of oxygen gas at the given conditions:
V(O2) = (n(O2) × R × T) / P
V(O2) = (4.994 mol × 0.08206 L·atm/(mol·K) × 298.15 K) / 1.00 atm = 122.1 L
The total volume of the mixture of hydrogen and oxygen gas can be found by adding the volumes of hydrogen and oxygen:
V(total) = V(H2) + V(O2) = 243.9 L + 122.1 L = 366 L. Therefore, the correct answer is (C).

Question 3

If the molar mass of monoatomic deuterium (D)is 2.0141 grams then what is the density of diatomic deuterium (D₂)gas at 25.0°C and 1.00 atmosphere pressure? A)0)082 g/L B)0)165 g/L C)0)329 g/L D)12.2 g/L

Accepted Answer

The molar mass of diatomic deuterium (D₂) is twice the molar mass of monoatomic deuterium, which is 4.0282 g. Using the ideal gas law, PV = nRT, we can calculate the density of the gas: density = (molar mass) * (pressure) / (gas constant) * (temperature) density = (4.0282 g/mol) * (1 atm) / (0.08206 L atm/mol K) * (298 K) density = 0.165 g/L Therefore, the best choice is B.

Question 4

Hydrogen,H₂,has a very low boiling point.What is the force that must be overcome in order to boil hydrogen? A)dipole-dipole B)H-H covalent bonding C)hydrogen bonding D)London dispersion

Accepted Answer

Hydrogen only has London dispersion forces because of its small size and low polarizability. Therefore, the force that must be overcome in order to boil hydrogen is London dispersion.

Question 5

The strongest homonuclear single bond is
A)H-H
B)C-C
C)N-N
D)O-O

Accepted Answer

The H-H bond is the strongest homonuclear single bond due to the small size of the hydrogen atom, which allows for effective overlap of the 1s orbitals, resulting in a strong covalent bond.

Question 6

What is not a commercial method for the preparation of hydrogen gas? A)H₂O(g)+ CH₄(g)→ CO(g)+ 3 H₂(g) B)2 H₂O(l)→ 2 H₂(g)+ O₂(g) C)H₂O(g)+ C(s)→ CO(g)+ H₂(g) D)4 H₂O(g)+ 3 Fe → Fe₃O₄(s)+ 4 H₂(g)

Accepted Answer

Electrolysis of water (option B) is not commonly used commercially due to its high energy consumption compared to other methods.

Question 7

How many grams of zinc metal are required to produce 1.00 liter of hydrogen gas at STP according to the chemical equation shown below? 
A)0)0343 g
B)2)92 g
C)5)84 g
D)65.4 g

Accepted Answer

According to the chemical equation shown below, 1 mole of zinc produces 1 mole of hydrogen. At STP, 1 mole of any ideal gas occupies 22.4 L.
Zn + 2HCl → ZnCl2 + H2
1 mole of H2 gas at STP occupies 22.4 L
1 liter of H2 gas at STP = 0.0446 mol
So, to produce 1 liter of H2 gas at STP, 0.0446 mol of zinc is required.
The molar mass of zinc is 65.4 g/mol
Therefore, mass of zinc required = 0.0446 x 65.4 = 2.92 g.

Question 8

Which is an ionic binary hydride?
A)HCl
B)KH
C)both HCl and KH
D)neither HCl nor KH

Accepted Answer

An ionic binary hydride is formed between a metal and hydrogen. In option B, KH is formed between potassium (metal) and hydrogen, making it an ionic binary hydride. HCl is a covalent binary hydride as it is formed between non-metal hydrogen and non-metal chlorine. Therefore, the correct answer is B.

Question 9

How many liters of hydrogen gas are needed to produce 90.0 grams of water at 25.0°C and 1.00 atm pressure according to the chemical equation shown below? 2 H₂(g)+ O₂(g)→ 2 H₂O(l) A)61.1 L B)122 L C)183 L D)366 L

Accepted Answer

To find the volume of hydrogen gas needed, first calculate the moles of water produced: 90.0 g H2O / 18.015 g/mol = 5.0 mol H2O. According to the balanced equation, 2 moles of H2 produce 2 moles of H2O, so 5.0 mol H2O requires 5.0 mol H2. Using the ideal gas law (PV=nRT), where R=0.0821 L·atm/mol·K and T=298 K (25°C), the volume V = nRT/P = (5.0 mol)(0.0821 L·atm/mol·K)(298 K) / (1.00 atm) = 122 L.

Question 10

How many kilojoules of energy are released when 90.0 grams of water are produced in the reaction shown below? 2 H₂(g)+ O₂(g)→ 2 H₂O(l)ΔH° = -572 kJ A)5720 kJ B)2860 kJ C)1430 kJ D)715 kJ

Accepted Answer

The reaction produces 2 moles of water with ΔH° = -572 kJ. The molar mass of water is 18 g/mol, so 90 g of water is 5 moles. Therefore, the energy released is (5/2) * 572 kJ = 1430 kJ.

Question 11

The dissociation of D₂O is shown below. D₂O ⇌ D⁺(aq)+ OD^-(aq)K = 1.95 × 10^-15 at 25°C In order to be acidic a D₂O solution must have a pH (= pD)that is A)greater than 7.00 B)greater than 7.35 C)less than 7.00 D)less than 7.35

Accepted Answer

The dissociation of D₂O produces H+ ions, making the solution acidic. The equilibrium constant for the dissociation reaction is relatively small (1.95 × 10^-15), indicating that the concentration of H+ ions in the solution will be low. This means that the pH of the solution will be less than 7.35, making choice D the best option.

Question 12

Which isotope of diatomic hydrogen should have the highest heat of vaporization? A)H₂ B)D₂ C)T₂ D)The values are equal.

Accepted Answer

T₂ (tritium) has the highest mass among the isotopes, leading to stronger intermolecular forces and thus a higher heat of vaporization compared to H₂ and D₂.

Question 13

The largest single industrial use of hydrogen is
A)in the synthesis of methanol.
B)in the synthesis of ammonia.
C)in the hydrogenation of fats and oils.
D)as an automobile fuel.

Accepted Answer

The largest single industrial use of hydrogen is in the synthesis of ammonia, which is used to produce fertilizers and other chemicals. Hydrogenation of fats and oils and use as an automobile fuel are also important applications of hydrogen, but they do not constitute the largest industrial use. Although hydrogen can be used in the synthesis of methanol, this application is not as widespread as ammonia synthesis.

Question 14

Differences in the physical properties of H₂O and D₂O are due to isotope effects.Which comparison is not correct? Compared to H₂O,D₂O has a higher A)boiling point. B)density. C)dissociation constant. D)melting point.

Accepted Answer

Isotope effects do not significantly affect dissociation constants, so the comparison of dissociation constants between the two molecules is not applicable. The other physical properties, such as boiling point, density, and melting point, can be affected by isotope effects.

Question 15

Write a chemical equation representing the water gas shift reaction. A)H₂O(g)+ CH₄(g)→ CO(g)+ 3 H₂(g) B)2 H₂O(l)→ 2 H₂(g)+ O₂(g) C)CO(g)+ H₂O(g)→ CO₂(g)+ H₂(g) D)4 H₂O(g)+ 3 Fe → Fe₃O₄(s)+ 4 H₂(g)

Accepted Answer

The water gas shift reaction involves the reaction between carbon monoxide and water vapor to produce carbon dioxide and hydrogen gas. The balanced chemical equation for this reaction is CO(g) + H2O(g) → CO2(g) + H2(g), which is equivalent to option C when H₂O is substituted for H2O and H₂ is substituted for H2.

Question 16

What is the Lewis electron dot structure for the hydride ion? A)H⁺ B)H: ^- C)H ∙ D)H₃O⁺

Accepted Answer

The Lewis electron dot structure for the hydride ion is a hydrogen atom with a single valence electron and a negative charge represented by a dot next to the hydrogen symbol: H:

Question 17

The first step in the steam-hydrocarbon re-forming process is shown below. H₂O(g)+ CH₄(g)→ CO(g)+ 3 H₂(g What is the change in oxidation number of the atom undergoing oxidation in this reaction? A)- 2 B)+ 1 C)+ 2 D)+ 6

Accepted Answer

The answer of The first step in the steam-hydrocarbon re-forming...

Question 18

How many grams of H₂ gas gas can be produced by the reaction of 27.0 grams of Al(s)with an excess of dilute hydrochloric acid in the reaction shown below? 2 Al(s)+ 6 HCl(aq)→ 2 AlCl₃(aq)+ 3 H₂(g) A)1)34 g B)2)02 g C)3)03 g D)6)06 g

Accepted Answer

To determine the grams of gas produced, we need to calculate the moles of gas produced using stoichiometry.

First, calculate the moles of Al(s) using its molar mass of 26.98 g/mol:
27.0 g Al × (1 mol Al/26.98 g Al) = 1.00 mol Al

Since the reaction ratio between Al(s) and H2(g) is 2:3, we can use the mole of Al(s) to calculate the moles of H2(g):
1.00 mol Al × (3 mol H2/2 mol Al) = 1.50 mol H2

Now that we have the moles of H2(g), we can use its molar mass of 2.02 g/mol to calculate the grams of H2(g) produced:
1.50 mol H2 × (2.02 g H2/1 mol H2) = 3.03 g H2

Therefore, the answer is (C) 3.03 g.

Question 19

Consider the hypothetical isotope of hydrogen,quadrium,Q = ⁴H.Q₂O would have a melting point that is (higher,lower)and a dissociation constant K_w that is (larger smaller)than H₂O. A)higher,larger B)higher,smaller C)lower,larger D)lower,smaller

Accepted Answer

Quadrium (Q) is heavier than regular hydrogen, leading to stronger hydrogen bonds in Q2O, resulting in a higher melting point and a smaller dissociation constant Kw compared to H2O.

Question 20

Which individual is generally given credit for the discovery of hydrogen gas?
A)Cavendish
B)Davy
C)Lavoisier
D)Priestley

Accepted Answer

Henry Cavendish is credited with the discovery of hydrogen gas in 1766.

Quiz 18: Hydrogen, oxygen, and Water

Which is not an isotope of hydrogen?

What is the total volume of the mixture of hydrogen gas and oxygen gas can be obtained from the electrolysis of 90.0 grams of water at 25.0°C and 1.00 atm pressure according to the chemical equation shown below? 2 H₂O(l) 2 H₂(g) + O₂(g)

If the molar mass of monoatomic deuterium (D) is 2.0141 grams then what is the density of diatomic deuterium (D₂) gas at 25.0°C and 1.00 atmosphere pressure?

Hydrogen,H₂,has a very low boiling point.What is the force that must be overcome in order to boil hydrogen?

The strongest homonuclear single bond is

What is not a commercial method for the preparation of hydrogen gas?

How many grams of zinc metal are required to produce 1.00 liter of hydrogen gas at STP according to the chemical equation shown below?

Which is an ionic binary hydride?

How many liters of hydrogen gas are needed to produce 90.0 grams of water at 25.0°C and 1.00 atm pressure according to the chemical equation shown below? 2 H₂(g) + O₂(g) → 2 H₂O(l)

How many kilojoules of energy are released when 90.0 grams of water are produced in the reaction shown below? 2 H₂(g) + O₂(g) → 2 H₂O(l) ΔH° = -572 kJ

The dissociation of D₂O is shown below. D₂O ⇌ D⁺(aq) + OD^-(aq) K = 1.95 × 10^-15 at 25°C In order to be acidic a D₂O solution must have a pH (= pD) that is

Which isotope of diatomic hydrogen should have the highest heat of vaporization?

The largest single industrial use of hydrogen is

Differences in the physical properties of H₂O and D₂O are due to isotope effects.Which comparison is not correct? Compared to H₂O,D₂O has a higher

Write a chemical equation representing the water gas shift reaction.

What is the Lewis electron dot structure for the hydride ion?

The first step in the steam-hydrocarbon re-forming process is shown below. H₂O(g) + CH₄(g) → CO(g) + 3 H₂(g What is the change in oxidation number of the atom undergoing oxidation in this reaction?

How many grams of H₂ gas gas can be produced by the reaction of 27.0 grams of Al(s) with an excess of dilute hydrochloric acid in the reaction shown below? 2 Al(s) + 6 HCl(aq) → 2 AlCl₃(aq) + 3 H₂(g)

Consider the hypothetical isotope of hydrogen,quadrium,Q = ⁴H.Q₂O would have a melting point that is (higher,lower) and a dissociation constant K_w that is (larger smaller) than H₂O.

Which individual is generally given credit for the discovery of hydrogen gas?

Quiz 18: Hydrogen, oxygen, and Water

Which is not an isotope of hydrogen?

What is the total volume of the mixture of hydrogen gas and oxygen gas can be obtained from the electrolysis of 90.0 grams of water at 25.0°C and 1.00 atm pressure according to the chemical equation shown below? 2 H2O(l) 2 H2(g) + O2(g)

If the molar mass of monoatomic deuterium (D) is 2.0141 grams then what is the density of diatomic deuterium (D2) gas at 25.0°C and 1.00 atmosphere pressure?

Hydrogen,H2,has a very low boiling point.What is the force that must be overcome in order to boil hydrogen?