Rate of reaction of hydrogen with liquid lithium: comparison with sodium and potassium
Abstract
Rates of reaction of hydrogen with a clean liquid-lithium surface have been determined at 217, 244, 257, 270, and 295 °C at pressures up to 23.7 kN m–2. The rates range from 4.683 × 106 to 27.919 × 106 mm s–1(kN m–2)–1 at 217 and 295 °C respectively. The reaction is first order with an activation energy of 52.8 kJ mol–1 which is lower than that for potassium (66.5 U mol–1) and sodium (72.4 kJ mol–1). Liquid lithium reacts more rapidly than do these metals; the rates at 250 °C for Li, K, and Na are in the nearest whole number ratio of 43 : 4 : 1. The results are consistent with a report that small additions of lithium to sodium enhance the rate of hydrogen absorption.