In the CRW exercise with Sodium Aluminum Sulphate and water, which hazard is predicted?

• A. Reaction products may be toxic
• B. Reaction products may be corrosive
• C. Exothermic reaction at ambient temperatures
• D. Reaction generates gas that may cause pressurization

Answer: (D)

The key idea here is that some solid salts reacting with water can release a gas as part of the reaction. In the CRW scenario with sodium aluminum sulfate, the analysis predicts that gas will be formed during or as a result of the contact with water. If this reaction occurs in a closed or poorly vented container, the gas buildup can pressurize the vessel, creating a physical hazard from pressure rather than from heat, toxicity, or corrosivity of the products alone. The emphasis is on the potential for gas evolution to cause pressurization, which is why this option is considered the best answer. The other possibilities—toxic or corrosive products, or an exothermic reaction at room temperature—are not the primary hazard described in this case, though some heat or hazardous products could occur in different contexts.