called as

1a All minerals and metals are called material nouns.
1b. All minerals and metals are called as material nouns.
2a. We call him Mohan.
2b. We call him as Mohan.
3a. We elect him the president of our club.
3b. We elect him as the president of our club.
Are all correct?
Please comment. Thanks.

Not a teacher. Not a native speaker.

I think:
All minerals and metals are called material nouns.
We call him Mohsin.
We elect him as the president of our club.

  1. All minerals and metals are types of materials.
    All minerals and metals are classified as materials.
  2. We call him Mohan.
  3. both forms are okay providing you are indicating what is happening as you speak, which would be unusual. The past tense would usually be required.