Question

Why does Earth have so little carbon dioxide in its atmosphere compared to Venus? Earth has just as much carbon dioxide as Venus, but most of it is locked up in carbonate rocks

Answer 1

Earth has lost a vast more amount of gas due to thermal escape than has Venus. Because of its lack of magnetic field, Venus has had the ability to gain gas through the impacts of solar wind particles, meanwhile Earth has not gained gas in this like this. Most of the gases that have been put out by volcanoes on Earth later returned to the surface.