Safety Hazard of Hydrogen Storage

Steps:

• Recall that hydrogen-oxygen fuel cells produce electricity via H₂ + ½O₂ → H₂O, powering the car cleanly.
• Identify potential disadvantages: hydrogen's high flammability and storage challenges in high-pressure tanks.
• Evaluate options: A relates to fossil fuels, not hydrogen; C misstates the water byproduct; D is neutral as air-sourced oxygen is abundant.
• Select B as it highlights the explosion risk from tank rupture in crashes.

Why B is correct:

• Hydrogen is stored compressed at high pressures; rupture in an accident releases flammable gas that ignites easily, causing explosions (per flammability limits: 4-75% in air).

Why the others are wrong:

• A: Applies to gasoline vehicles, irrelevant to renewable hydrogen fuel cells.
• C: Reaction product is water (H₂O), which is non-toxic.
• D: Sourcing oxygen from air is efficient and cost-free, not a disadvantage.

Final answer: B