Total number of elements which do not form hydrides are Mo, Ca, Fe, Pd, Co, Ru, W, Cr

The element which forms only one hydride is :

The element which forms only one hydride is :

What type of elements do form saline hydrides ?

Among the following number of elements, which are transition elements are: Ce, Nd, Sm, Yb, Ru, Th, U, Np, Am

Which type of elements form ionic hydrides hydrides

Which type of elements form interstitial hydrides?