Now, any compound that's composed of two elements in which one element is a hydrogen is called a Hydride. Now, Hydrides have varying levels of acidity. They could be acidic, neutral, or basic. Now, if we look at our emeritus table, we see a trend. We see that as we go across the period from left to right, the acidity of Hydrides increases. And as we go down a group, the acidity of Hydride also increases.