Simple Batch Apex with Schedule Class

Batch Class

global class BatchClass implements Database.Batchable<sobject>
{
        global Database.QueryLocator start(Database.BatchableContext BC){
             String Query='Select LastName,Id from Lead';
              return Database.getQueryLocator(Query);
        }

        global void Execute(Database.BatchableContext BC,List<sobject> Scope){

                List<Lead> ld = Scope;

                for(Lead l: ld){

                        l.LastName = l.LastName+'Batch testing';

               }

        }

        global void finish(Database.BatchableContext BC){     

     }

}

Schedule Class

global class ScheduleClass implements Schedulable {
   global void execute(SchedulableContext sc) {
      BatchClass  b = new BatchClass(); 
      database.executebatch(b);
   }
}