Molekule wants to clean up the world’s air, using one personal molecular air purifier at a time. That’s why it has raised $25 million in a funding round led by Foundry Group. The San Francisco company has special personal air filters that it says can eliminate the full spectrum of indoor air pollutants, breaking them down on a molecular level. The product is one of a series of Internet-connected devices that detects the quality of the air we breathe, and it’s one more expression of the Internet of Things, or smart and connected everyday devices.