Question 1:

To determine the total number of moles of ions present in 8.0 g of sodium hydroxide (NaOH), follow these steps:

1. Calculate the moles of NaOH:

• Molar mass of NaOH = 23 (Na) + 16 (O) + 1 (H) = 40 g/mol

• Moles of NaOH = mass / molar mass = 8.0 g / 40 g/mol = 0.2 mol

2. Determine the moles of ions produced when NaOH dissociates:

• NaOH dissociates completely in water:

  NaOH→Na⁺+OH⁻

• So, 1 mole of NaOH produces 2 moles of ions (1 mole of Na⁺ and 1 mole of OH⁻).

3. Calculate the total moles of ions:

• Total moles of ions = moles of NaOH × 2 = 0.2 mol × 2 = 0.4 mol

Answer: C. 0.4

*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 2:

To determine the mass of 0.100 moles of calcium hydroxide, Ca(OH)₂, follow these steps:

1. Calculate the molar mass of Ca(OH)₂:

   • Calcium (Ca): 40 g/mol

   • Oxygen (O): 16 g/mol × 2 = 32 g/mol

   • Hydrogen (H): 1 g/mol × 2 = 2 g/mol

   • Total molar mass = 40+32+2=74 40 + 32 + 2 = 74 g/mol

2. Calculate the mass for 0.100 moles:
   Mass=moles × molar mass=0.100 mol × 74 g/mol=7.40 g

The calculated mass is 7.40 g, which rounds to 7.41 g when considering significant figures (as the molar mass is exact and the moles are given to three decimal places).

Answer: D. 7.41g

*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 3:

To determine the number of hydrogen atoms in 0.10 mol of ethanol (C₂H₅OH):

1. Find the number of hydrogen atoms per molecule of ethanol:

   • The formula is C₂H₅OH, which has 6 hydrogen atoms (5 from C₂H₅ and 1 from OH).

2. Calculate the number of molecules in 0.10 mol:

   • Number of molecules = moles × Avogadro's number

   • 0.10 mol × 6.022×10²³ molecules/mol =6.022×10²² molecules

3. Calculate the number of hydrogen atoms:

   • Each molecule has 6 H atoms.

   • Total H atoms = 6.022×10²² ×6= 3.6132×10²³

   This rounds to 3.6 ×10²³

Answer: C. 3.6 × 10²³

*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 4:

To determine which compound contains the greatest number of hydrogen atoms in 1.0 g, we need to compare the number of hydrogen atoms per gram for each substance.

Step 1: Calculate the number of moles in 1.0 g for each compound.

• Molar mass of CH₄ = 12 + 4(1) = 16 g/mol

• Molar mass of CH₃Cl = 12 + 3(1) + 35.5 = 50.5 g/mol

• Molar mass of CH₂Cl₂ = 12 + 2(1) + 2(35.5) = 85 g/mol

• Molar mass of CHCl₃ = 12 + 1 + 3(35.5) = 119.5 g/mol

Step 2: Find the number of hydrogen atoms per mole for each compound.

• CH₄ has 4 H atoms per mole.

• CH₃Cl has 3 H atoms per mole.

• CH₂Cl₂ has 2 H atoms per mole.

• CHCl₃ has 1 H atom per mole.

Step 3: Calculate the number of hydrogen atoms in 1.0 g.
The number of H atoms = (mass / molar mass) × (number of H atoms per molecule) × Avogadro's number.

Since Avogadro's number is constant, we can compare:

So, compute (H atoms per molecule) / (molar mass) for each:

• For CH₄: 4/16=0.250

• For CH₃Cl: 3/50.5≈0.0594

• For CH₂Cl₂: 2/85≈0.0235

• For CHCl₃: 1/119.5≈0.00837

CH₄ has the highest value (0.250), so it has the greatest number of hydrogen atoms in 1.0 g.

Answer: A. 1.0g of CH₄

*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 5:

To find the number of moles of molecules in 400 g of methane (CH₄):

1. Calculate the molar mass of CH₄:

   • Carbon (C): 12 g/mol

   • Hydrogen (H): 1 g/mol × 4 = 4 g/mol

   • Total molar mass = 12 + 4 = 16 g/mol

2. Calculate the number of moles:

   Number of moles = (mass) / (molar mass) = 400 / 16 = 25 mol

So, there are approximately 25 moles of methane molecules.

Answer: C. 25

*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 6:

To determine the number of molecules in 4.5 g of water (H₂O):

1. Calculate the molar mass of water:

   • H₂O: 2(1) + 16 = 18 g/mol

2. Find the number of moles in 4.5 g:

   Moles=(mass) / (molar mass)=4.5/18=0.25mol

3. Calculate the number of molecules:

   • Use Avogadro's number: 6.022×10²³ molecules/mol

   Number of molecules = 0.25×6.022×10²³=1.5055×10²³

This is approximately 1.5 ×10²³ molecules.

Answer: A. 1.5 ×10²³

*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 7:

To find the molar mass of the compound:

Given:

• Number of moles = 0.200 mol

• Mass = 24.0 g

The molar mass (M ) is calculated as:

Answer: C. 120g mol⁻¹

*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 8:

To determine which sample contains the smallest number of atoms, we need to calculate the total number of atoms in each option.

Step 1: Calculate the number of moles for each substance.

• Use the formula: moles = mass / (molar mass)

Step 2: Find the number of molecules (or formula units) for each.

• Number of molecules = moles × Avogadro's number (N_A)

Step 3: Multiply by the number of atoms per molecule to get the total number of atoms.

Let's analyze each option:

A. 1.2 g of water (H₂O)

• Molar mass = 18 g/mol

• Moles = 1.2/18=0.0667 1.2/18 = 0.0667 mol

• Molecules = 0.0667×N_A

• Atoms per molecule = 3 (2H + 1O)

• Total atoms = 0.0667×N_A×3=0.2001×N_A

B. 1.8 g of carbon monoxide (CO)

• Molar mass = 28 g/mol

• Moles = 1.8/28=0.0643 1.8/28 = 0.0643 mol

• Molecules = 0.0643×N_A

• Atoms per molecule = 2 (1C + 1O)

• Total atoms = 0.0643 × N_A×2 = 0.1286 × N_A

C. 24 g of glucose (C₆H₁₂O₆)

• Molar mass = 180 g/mol

• Moles = 24/180=0.1333 24/180 = 0.1333 mol

• Molecules = 0.1333×N_A

• Atoms per molecule = 24 (6C + 12H + 6O)

• Total atoms = 0.1333×N_A× 24 = 3.1992 × N_A

D. 3.9 g of ammonia (NH₃)

• Molar mass = 17 g/mol

• Moles = 3.9/17=0.2294 3.9/17 = 0.2294 mol

• Molecules = 0.2294×NA 0.2294 × N_A​

• Atoms per molecule = 4 (1N + 3H)

• Total atoms = 0.2294×N_A×4=0.9176×N_A

Compare the total atoms (in terms of N_A​ ):

• A: 0.2001×NA 0.2001 ×N_A

• B: 0.1286×NA 0.1286 ×N_A

• C: 3.1992×NA 3.1992 × N_A

• D: 0.9176×NA 0.9176 ×N_A

The smallest is B: 0.1286×N_A

Answer: B. 1.8g of carbon monoxide

*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 9:

To determine the number of atoms in 640 g of methanol (CH₃OH), follow these steps:

1. Calculate the molar mass of CH₃OH:

   • Carbon (C): 12 g/mol

   • Hydrogen (H): 1 g/mol × 4 = 4 g/mol (3 from CH₃ and 1 from OH)

   • Oxygen (O): 16 g/mol

   • Total molar mass = 12 + 4 + 16 = 32 g/mol

2. Find the number of moles in 640 g:

   Moles=640 / 32=20 mol

3. Determine the number of molecules:

   Number of molecules = moles × Avogadro's number N_A

   Number of molecules=20×6.022×10²³=1.2044×10²⁵
   
   
   
4. Calculate the total number of atoms:

   Each molecule of CH₃OH has 6 atoms (1 C, 4 H, 1 O).

   Total atoms = number of molecules × atoms per molecule

   Total atoms=(1.2044×10²⁵)×6=7.2264×10²⁵

   This is approximately 7.20 ×10²⁵

Answer: D. 7.20 ×10²⁵

*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.

Question 10:

To determine the number of ions in 2.0 moles of sodium sulfate (Na₂SO₄), follow these steps:

1. Understand the dissociation of Na₂SO₄:

   • Sodium sulfate dissociates completely in water:

     Na₂SO₄ → 2Na⁺+SO₄^2-

   • So, 1 mole of Na₂SO₄ produces 3 moles of ions (2 moles of Na⁺ and 1 mole of SO₄²⁻).

2. Calculate the total moles of ions in 2.0 moles of Na₂SO₄:
   
   Total moles of ions=2.0 mol×3=6.0 mol
   
   
   
3. Convert moles of ions to number of ions:

   Use Avogadro's number: 6.022×10²³ ions per mole.

   Number of ions=6.0×6.022×10²³ =3.6132×10²⁴

   This is approximately 3.6×10²⁴

Answer: B. 3.6×10²⁴

*These A.I. responses have been individually checked to ensure they match the accepted answer, but explanations may still be incorrect. Responses may give guidance but the A.I. might not be able to answer the question! This is particularly the case for questions based on diagrams, which the A.I. typically cannot interpret.
Grade Gorilla uses Gemini, Deepseek and a range of other A.I. chatbots to generate the saved responses. Some answers have had human intervention for clarity or where the A.I. has not been able to answer the question.