Chattanooga, Tennessee is 1,307 times larger than Mobile, Alabama.
Area: 0 km2 calculated
Mobile is the county seat of Mobile County, Alabama. The population within the city limits was 195,111 as of the 2010 United States Census, making it the third most populous city in the U.S. Wikipedia
Area: 390 km2 calculated
Chattanooga is the fourth-largest city in the U.S. state of Tennessee, with a population of 167,674 as of the 2010 census, and an estimated population of 171,279 in 2012. It is the seat of Hamilton County. Wikipedia