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_2068719_1 ( δs_ VARCHAR, _butadiene VARCHAR )

### Question ###
Name the number of s /cal mol 1 k 1 for butadiene being 1,2-dimethylene-cyclohexane

### Accurate SQL ###

SELECT COUNT(δs_) AS ‡__cal_mol_−1_k_−1 FROM table_2068719_1 WHERE _butadiene = "1,2-dimethylene-cyclohexane"