Which two elements combine to form the most abundant salt found in seawater?

• A. Magnesium and oxygen
• B. Potassium and bromine
• C. Sodium and chlorine
• D. Calcium and sulfur

Answer: (C)

Verified step by step guidance

1. Understand that the most abundant salt in seawater is common table salt, which is chemically known as sodium chloride (NaCl).
2. Recall that sodium chloride is formed by the combination of sodium (Na) and chlorine (Cl) elements.
3. Recognize that sodium is a metal and chlorine is a nonmetal, and they combine through ionic bonding to form NaCl.
4. Note that other pairs like magnesium and oxygen or potassium and bromine form different compounds, but not the most abundant salt in seawater.
5. Conclude that the correct pair of elements forming the most abundant salt in seawater is sodium and chlorine.