C832 Chemistry with Lab
Access The Exact Questions for C832 Chemistry with Lab
💯 100% Pass Rate guaranteed
🗓️ Unlock for 1 Month
Rated 4.8/5 from over 1000+ reviews
- Unlimited Exact Practice Test Questions
- Trusted By 200 Million Students and Professors
Starting from
$30/month
What’s Included:
- Unlock 100 + Actual Exam Questions and Answers for C832 Chemistry with Lab on monthly basis
- Well-structured questions covering all topics, accompanied by organized images.
- Learn from mistakes with detailed answer explanations.
- Easy To understand explanations for all students.
Access and unlock Multiple Practice Question for C832 Chemistry with Lab to help you Pass at ease.
Free C832 Chemistry with Lab Questions
1. A student's clothing catches fire from the flame of a "Bunsen" burner. What should you do first?
- Tell the student to stop, drop, and roll.
- Use a paper towel to pat out the flames.
- Run to get water from the sink.
- Tell the student to wave their arms to extinguish the fire.
Explanation
Explanation:
If a student’s clothing catches fire, the immediate and correct action is to tell the student to stop, drop, and roll. This technique cuts off the oxygen supply to the flames and helps extinguish the fire quickly.
Why the other options are incorrect:
Running or waving arms fans the flames and can worsen the burn, while using a paper towel or water from the sink is ineffective and may spread the fire. If available, a fire blanket or safety shower can also be used after the student has dropped to the floor. Quick action and calm instructions are critical to prevent severe injury.
If a student’s clothing catches fire, the immediate and correct action is to tell the student to stop, drop, and roll. This technique cuts off the oxygen supply to the flames and helps extinguish the fire quickly.
Why the other options are incorrect:
Running or waving arms fans the flames and can worsen the burn, while using a paper towel or water from the sink is ineffective and may spread the fire. If available, a fire blanket or safety shower can also be used after the student has dropped to the floor. Quick action and calm instructions are critical to prevent severe injury.
2. In the Lewis structure of XeF₄, how many lone pairs are on xenon?
- 0
- 1
- 2
- 3
Explanation
Explanation:
Xenon tetrafluoride (XeF4) has xenon as the central atom with six valence electrons. It forms four single bonds with fluorine atoms. After accounting for the bonding electrons, two lone pairs remain on xenon. The lone pairs occupy positions opposite each other in the octahedral electron geometry to minimize repulsion, resulting in a square planar molecular geometry.
Why the other options are incorrect:
0 lone pairs would imply all electrons used in bonding without octet expansion; 1 lone pair does not account for xenon's valence electrons fully; 3 lone pairs would suggest a different electron count and geometry.
Xenon tetrafluoride (XeF4) has xenon as the central atom with six valence electrons. It forms four single bonds with fluorine atoms. After accounting for the bonding electrons, two lone pairs remain on xenon. The lone pairs occupy positions opposite each other in the octahedral electron geometry to minimize repulsion, resulting in a square planar molecular geometry.
Why the other options are incorrect:
0 lone pairs would imply all electrons used in bonding without octet expansion; 1 lone pair does not account for xenon's valence electrons fully; 3 lone pairs would suggest a different electron count and geometry.
3. Which substance is nonpolar despite having polar bonds?
- a) HF
- b) CCl₄
- c) NH₃
- d) SO₂
Explanation
Although each C–Cl bond in carbon tetrachloride (CCl₄) is polar due to the electronegativity difference between carbon and chlorine, the molecule’s tetrahedral symmetry causes the bond dipoles to cancel out. As a result, there is no net dipole moment, and the molecule is overall nonpolar. In contrast, HF, NH₃, and SO₂ all have net dipoles because of their asymmetrical structures.
Correct Answer: CCl₄
Correct Answer: CCl₄
4. What type of reaction is Pb(NO₃)₂ + 2KI → PbI₂ + 2KNO₃?
- Synthesis
- Decomposition
- Double displacement
- Combustion
Explanation
Explanation:
Correct Answer: Double displacement
Why the other options are incorrect:
Synthesis combines reactants; decomposition breaks down; combustion involves oxygen and energy release.
Correct Answer: Double displacement
Why the other options are incorrect:
Synthesis combines reactants; decomposition breaks down; combustion involves oxygen and energy release.
5. The correct formula for ammonium phosphate is:
- NH₄PO₄
- (NH₄)₃PO₄
- NH₄(PO₄)₃
- (NH₄)₂PO₄
Explanation
Explanation:
The correct formula for ammonium phosphate is (NH₄)₃PO₄. The ammonium ion (NH₄⁺) carries a +1 charge, and the phosphate ion (PO₄³⁻) carries a -3 charge. To balance the charges, three ammonium ions are required for each phosphate ion, resulting in the formula (NH₄)₃PO₄. This compound is commonly used as a fertilizer due to its high nitrogen and phosphorus content.
Correct Answer: (NH₄)₃PO₄
The correct formula for ammonium phosphate is (NH₄)₃PO₄. The ammonium ion (NH₄⁺) carries a +1 charge, and the phosphate ion (PO₄³⁻) carries a -3 charge. To balance the charges, three ammonium ions are required for each phosphate ion, resulting in the formula (NH₄)₃PO₄. This compound is commonly used as a fertilizer due to its high nitrogen and phosphorus content.
Correct Answer: (NH₄)₃PO₄
6. The formula for magnesium nitride is:
- MgN
- Mg₃N₂
- Mg₂N₃
- MgN₂
Explanation
Explanation:
The correct formula for magnesium nitride is Mg₃N₂. Magnesium forms a +2 ion (Mg²⁺), and nitrogen forms a -3 ion (N³⁻). To balance the charges, three magnesium ions (total +6) combine with two nitrogen ions (total -6), forming the neutral compound Mg₃N₂. This compound is an ionic solid commonly produced when magnesium reacts directly with nitrogen gas.
Correct Answer: Mg₃N₂
The correct formula for magnesium nitride is Mg₃N₂. Magnesium forms a +2 ion (Mg²⁺), and nitrogen forms a -3 ion (N³⁻). To balance the charges, three magnesium ions (total +6) combine with two nitrogen ions (total -6), forming the neutral compound Mg₃N₂. This compound is an ionic solid commonly produced when magnesium reacts directly with nitrogen gas.
Correct Answer: Mg₃N₂
7. Balance the equation in acidic solution: __Cr₂O₇²⁻ + __Fe²⁺ → __Cr³⁺ + __Fe³⁺
Coefficient for Fe²⁺ is:
Coefficient for Fe²⁺ is:
- 3
- 6
- 14
- 7
Explanation
Explanation:
In acidic solution, the dichromate ion (Cr₂O₇²⁻) is reduced to Cr³⁺ while Fe²⁺ is oxidized to Fe³⁺. Balancing the half-reactions: Cr₂O₇²⁻ + 14 H⁺ + 6 e⁻ → 2 Cr³⁺ + 7 H₂O and Fe²⁺ → Fe³⁺ + e⁻. To balance the electrons, 6 Fe²⁺ ions are required to provide 6 electrons. Thus, the coefficient for Fe²⁺ in the balanced redox reaction is 6.
Why the other options are incorrect:
3 is half the required electrons; 14 is the coefficient for H⁺ in the reduction half-reaction; 7 is for H₂O in the reduction half-reaction.
Correct Answer: 6
In acidic solution, the dichromate ion (Cr₂O₇²⁻) is reduced to Cr³⁺ while Fe²⁺ is oxidized to Fe³⁺. Balancing the half-reactions: Cr₂O₇²⁻ + 14 H⁺ + 6 e⁻ → 2 Cr³⁺ + 7 H₂O and Fe²⁺ → Fe³⁺ + e⁻. To balance the electrons, 6 Fe²⁺ ions are required to provide 6 electrons. Thus, the coefficient for Fe²⁺ in the balanced redox reaction is 6.
Why the other options are incorrect:
3 is half the required electrons; 14 is the coefficient for H⁺ in the reduction half-reaction; 7 is for H₂O in the reduction half-reaction.
Correct Answer: 6
8. Balance the equation: __C₃H₈ + __O₂ → __CO₂ + __H₂O
- a) 1, 5, 3, 4
- b) 2, 10, 6, 8
- c) 1, 3, 3, 4
- d) 1, 10, 6, 8
Explanation
To balance the combustion of propane (C₃H₈), count the atoms of each element on both sides. Propane contains 3 carbon atoms and 8 hydrogen atoms. Therefore, 3 CO₂ molecules are needed to balance carbon, and 4 H₂O molecules to balance hydrogen. This results in a total of 10 oxygen atoms on the product side (6 from CO₂ and 4 from H₂O), requiring 5 O₂ molecules on the reactant side. The balanced equation is:
C₃H₈ + 5O₂ → 3CO₂ + 4H₂O.
Correct Answer: 1, 5, 3, 4
C₃H₈ + 5O₂ → 3CO₂ + 4H₂O.
Correct Answer: 1, 5, 3, 4
9. Name the molecular compound N₂O₅.
- Nitrogen oxide
- Dinitrogen pentoxide
- Nitrogen pentoxide
- Dinitrogen monoxide
Explanation
Explanation:
The correct name for N₂O₅ is dinitrogen pentoxide. In molecular compounds, prefixes are used to indicate the number of atoms of each element present. “Di-” means two nitrogen atoms, and “penta-” means five oxygen atoms. The final “a” in “penta-” is dropped before a word beginning with a vowel, making it “pentoxide.” This compound is known for being a strong oxidizing agent and an acid anhydride of nitric acid.
Correct Answer: Dinitrogen pentoxide
The correct name for N₂O₅ is dinitrogen pentoxide. In molecular compounds, prefixes are used to indicate the number of atoms of each element present. “Di-” means two nitrogen atoms, and “penta-” means five oxygen atoms. The final “a” in “penta-” is dropped before a word beginning with a vowel, making it “pentoxide.” This compound is known for being a strong oxidizing agent and an acid anhydride of nitric acid.
Correct Answer: Dinitrogen pentoxide
10. In the reaction N₂ + 3H₂ → 2NH₃, how many moles of NH₃ are produced from 4 moles of H₂?
- a) 2.67 mol
- b) 4 mol
- c) 1.33 mol
- d) 8 mol
Explanation
Explanation:
From the balanced chemical equation, 3 moles of hydrogen (H₂) produce 2 moles of ammonia (NH₃). To find how much NH₃ is produced from 4 moles of H₂, set up a proportion: (2 mol NH₃ / 3 mol H₂) × 4 mol H₂ = 8/3 mol NH₃ = 2.67 mol NH₃. Therefore, 2.67 moles of ammonia are produced from 4 moles of hydrogen gas.
Correct Answer: 2.67 mol
Why the other options are incorrect:
4 mol assumes 1:1 ratio; 1.33 mol is half; 8 mol doubles incorrectly.
From the balanced chemical equation, 3 moles of hydrogen (H₂) produce 2 moles of ammonia (NH₃). To find how much NH₃ is produced from 4 moles of H₂, set up a proportion: (2 mol NH₃ / 3 mol H₂) × 4 mol H₂ = 8/3 mol NH₃ = 2.67 mol NH₃. Therefore, 2.67 moles of ammonia are produced from 4 moles of hydrogen gas.
Correct Answer: 2.67 mol
Why the other options are incorrect:
4 mol assumes 1:1 ratio; 1.33 mol is half; 8 mol doubles incorrectly.
How to Order
1
Select Your Exam
Click on your desired exam to open its dedicated page with resources like practice questions, flashcards, and study guides.Choose what to focus on, Your selected exam is saved for quick access Once you log in.
2
Subscribe
Hit the Subscribe button on the platform. With your subscription, you will enjoy unlimited access to all practice questions and resources for a full 1-month period. After the month has elapsed, you can choose to resubscribe to continue benefiting from our comprehensive exam preparation tools and resources.
3
Pay and unlock the practice Questions
Once your payment is processed, you’ll immediately unlock access to all practice questions tailored to your selected exam for 1 month .