Silex, MO has a population of 68 and is the 27,720th largest city in the United States. The population density is 352 per sq mi which is 308% higher than the Missouri average and 289% higher than the national average. The median age in Silex is 52 which is approximately 35% higher than the Missouri average of 38. In Silex, 21% of the population over 15 years of age are married, 100% speak English and 0% speak Spanish. 34% of Silex residents were born in Missouri, 66% were born out of state, 0% were born outside of the United States and 0% were foreign born.