Entity command execution exception was unhandled by user code in mvc

namespace MvcApplication6.Models
{
    [Table("tblEmployee")]
    public class Employee
    {
        public int EmployeeId { get; set; }
        public string Name { get; set; }
        public string Gender { get; set; }
        public string City { get; set; }
    }
}

public class EmployeeContext:DbContext
    {
      public  DbSet<employee>Employees{get;set;}
    }


EmployeeController

public ActionResult Details(int id)
{
EmployeeContext employeeContext = new EmployeeContext();
Employee employees= employeeContext.Employees.Single(emp => emp.EmployeeId == id);
return View(employees);
}
am getting ERROR at id i.e" entity command execution exception was unhandled by user code".
i mentioned connection string alsocould you please send me solution...

What I have tried:

am getting ERROR at id i.e" entity command execution exception was un handled by user code".
i mentioned connection string also could you please send me solution...</employee>