Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_15366768_1 ( isotopic_mass___u__ VARCHAR, nuclide VARCHAR )

### Question ###
What is the mass of the element with a nuclide that is 169 tm?

### Accurate SQL ###

SELECT isotopic_mass___u__ FROM table_15366768_1 WHERE nuclide = "169 Tm"