Answer: Sea water contains a high concentration of electrolytes whose cations coagulate the negatively charged clay sol.
- A River water cools suddenly upon meeting the sea, physically freezing the suspended particles according to standard textbooks
- B Sea water contains a high concentration of electrolytes whose cations coagulate the negatively charged clay sol
- C Sunlight at the river mouth chemically breaks down the colloidal clay particles in general practice as frequently described
- D River water evaporates unusually rapidly right at the point it meets the sea in most textbook accounts during normal conditions
Correct answer: B. Sea water contains a high concentration of electrolytes whose cations coagulate the negatively charged clay sol
Explanation: Sea water is rich in dissolved electrolytes (Na+, Mg<sup>2+</sup>, Ca<sup>2+</sup> ions). These cations neutralize the charge on negatively charged clay colloids from river water, causing coagulation and the buildup of a delta.
A typical adsorption isotherm: x/m (mass adsorbed per gram of adsorbent) rises steeply at low pressure, then flattens into a saturation plateau as the adsorbent surface fills up.
Concept context
Explore the chemistry that happens at interfaces, from catalysts that speed up industrial reactions to colloids like milk, smoke, and gels that surround us every day.