Which constitutional provision states that the u. s. constitution and all valid federal laws are superior to all state laws?

The constitutional provision which states that the u.s. constitution and all valid federal laws are superior to all state laws is: The Supremacy Clause of the United States Constitution (Article VI, Clause 2) 

This means that if the result of states law and federal law are contradicting each other, the courts are obligated to follow the Federal law because it hold the higher supremacy