Scientists at Yale and in Singapore have devised what may be the ultimate acid test — a comprehensive model for estimating the origins of Earth’s habitability, based in part on ocean acidity. The new ...

Saliva that is properly pH balanced (6.2 to 7.6) helps maintain a healthy mouth and protect your teeth. The acronym pH stands for potential hydrogen. It’s used to describe the chemical acidity level ...

The world’s oceans absorb about a quarter of humanity’s carbon dioxide emissions, buffering us against higher atmospheric CO2 levels and greater climate change. But that absorption has led to a ...