Question 1:

The unit for the amount of a substance in Chemistry is the mole (symbol: mol).

• Gram and kilogram are units of mass.

• Cubic decimeter (dm³) is a unit of volume.

So, the correct answer is: C

*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 calculate the relative formula mass (M_r) of MgCl₂:

• Atomic mass of Mg = 24

• Atomic mass of Cl = 35.5

Relative formula mass has no units (it is a ratio), so the correct option is A. 95 (not 95g, as grams are units of mass).

*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 find the molar mass of NaHCO₃, we add up the atomic masses of each element:

• Na = 23

• H = 1

• C = 12

• O = 16 (and there are 3 oxygen atoms)

Molar mass is expressed in grams per mole (g/mol), but in multiple-choice questions, it is often written as 84 g (implying 84 g/mol).

The correct choice is B. 84g.

*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:

The correct formula for calculating the number of moles of a compound is:

This means you divide the mass in grams by the relative formula mass.

• Option A is incorrect because it multiplies instead of divides.

• Options C and D use mass in kilograms, but the standard formula requires mass in grams (if you use kg, you must convert to grams first, or use molar mass in kg/mol, which is less common).

So, the correct answer is B.

*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, use the formula:

Given:

• Mass of NaOH = 10 g

• Molar mass (Mr) of NaOH = 40 g/mol

So, the correct answer is C. 0.25.

*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 find the mass, use the formula:

Given:

• Moles of CO₂ = 0.2 mol

• Molar mass (M_r) of CO₂ = 44 g/mol

So, the correct answer is A. 8.8g.

*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 calculate the relative formula mass (M_r) of ammonium nitrate (NH₄NO₃), we add up the atomic masses of all the atoms in the formula:

• N = 14 (there are 2 nitrogen atoms: one in NH₄ and one in NO₃)

• H = 1 (there are 4 hydrogen atoms)

• O = 16 (there are 3 oxygen atoms)

M_r=(2×14)+(4×1)+(3×16)

M_r=28+4+48=80

So, the correct answer is B. 80.

*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 find the number of moles of ammonium nitrate (NH₄NO₃) in 40 kg, use the formula:

Step 1: Convert mass to grams.
40 kg = 40 × 1000 = 40,000 g

Step 2: Use the molar mass from the previous question.
M_r of NH₄NO₃ = 80 g/mol

Step 3: Calculate moles.

So, the correct answer is C. 500.

*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 find the number of moles in 1.00 tonne of CO₂, use the formula:

Step 1: Convert mass to grams.
1.00 tonne = 1,000,000 g

Step 2: Molar mass of CO₂.
M_r of CO₂ = 12 + (2 × 16) = 44 g/mol

Step 3: Calculate moles.

So, the correct answer is C. 22 727.

*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 which contains the greatest number of atoms, we need to calculate the number of moles of atoms in each option (since 1 mole of any element contains the same number of atoms—Avogadro's number).

Option A: 2 moles of carbon
→ Number of moles of atoms = 2.0

Option B: 36g of carbon (A_r of C = 12)
→ Moles = 3612=3.0 moles of atoms

Option C: 0.5 moles of magnesium
→ Number of moles of atoms = 0.5

Option D: 48g of magnesium (A_r of Mg = 24)
→ Moles = 4824=2.0 moles of atoms

Comparison:

• A = 2.0 moles of atoms

• B = 3.0 moles of atoms

• C = 0.5 moles of atoms

• D = 2.0 moles of atoms

The greatest number of moles of atoms is 3.0 in option B.

*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.