Confusion regarding classification of hydrides

According to my book,hydrides are classified as Ionic/Saltlike/Saline Hydrides, Covalent/Molecular Hydrides and Metallic/Non-stochiometric/Interstitial Hydrides.


The explanation of my book is not very clear to me I am confused that if an S-block element & Hydrogen form a covalent compound, it will be Saline or Molecular Hydride? Same question for a P-block element which forms ionic bond with Hydrogen.


I will be grateful if you would help.




Hydrides of alkaline/alkaline earth elements are *almost*\* always ionic because the cations are very electropositive forming a strong ionic bond. Hence, they are called *ionic*/salt like hydrides


The hydrides of p-block elements are not very strong and are non-ionic, hence they are considered *covalent* hydrides.


\*The key word *almost* is because beryllium hydride is the only s-block hydride which is covalent. [$\ce{BeH2}$ is also the only known s-block hydride which can't be made by direction reaction of beryllium and hydrogen](https://chemistry.stackexchange.com/questions/96533/why-cant-beryllium-react-with-hydrogen-gas-directly-to-give-hydride) (unlike other s-block hydrides which are made by direct metal and hydrogen interaction)


Previous discussion: [Is lithium hydride a salt?](https://chemistry.stackexchange.com/questions/46509/is-lithium-hydride-a-salt)


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