Why does "GRANT SELECT ... TO Role;" not allow members of Role to SELECT? Please consider the following scenario on a Oracle 11g Database.
The user ADMIN performs the following:
CREATE USER Alice IDENTIFIED BY pwdalice;

GRANT CREATE SESSION TO Alice;

CREATE ROLE Viewer IDENTIFIED BY pwdviewer;

GRANT Viewer TO Alice;

GRANT SELECT ON Table_1 TO Viewer;

Then Alice logs into the database as 'Alice' and executes the following command:
SELECT * FROM Table_1;

Alice gets the following error:
SELECT * FROM Table_1
              *
ERROR at line 1:
ORA-00942: table or view does not exist

I thought that granting privileges to a role would enable its member-users to get those privileges. However, this scenario shows that it is not so. What am I missing here? How can I grant SELECT to Alice using a role?
Update:
Following the answers, tried 3 fixes with no success
1) Using Fully-qualified Table Names
I missed to include the schema name in  SELECT * FROM Table_1; command. However, even after adding the schema name as shown below, still the error comes.
Alice executes:
SELECT * FROM ADMIN.Table_1;

Gets the error:
SELECT * FROM ADMIN.Table_1
                     *
ERROR at line 1:
ORA-00942: table or view does not exist

2) Using a synonym for the fully-qualified table name
Unfortunately, this does not seem to solve the problem either.
Alice executes the following:
CREATE SYNONYM Syn_Table_1 FOR ADMIN.Table_1;
CREATE SYNONYM Syn_Table_1 FOR ADMIN.Table_1
*
ERROR at line 1:
ORA-01031: insufficient privileges

3) Altering the session
ALTER SESSION SET current_schema = ADMIN;

Session altered.

SELECT * FROM Table_1;

SELECT * FROM Table_1
              *
ERROR at line 1:
ORA-00942: table or view does not exist
In addition to ensuring you're in the right schema, try this one;
Once logged in as Alice, do: SET ROLE Viewer IDENTIFIED BY pwdviewer; 

For more see here