Server Administration :: Allocating Extent To A Clob Column Of A Table

I have a table with two clob columns and need to manually allocate space to the table and to its lob segment. Is the following command correct?

--to allocate extent to the table
alter table emp allocate extent;
--the table has columns named col1 and col2 which are clob
--to allocate extents to the columns
alter table emp modify lob (col1) (allocate extent (size 10m))
/
alter table emp modify lob (col2) (allocate extent (size 10m))
/