var pairs = new ArrayList() { new { id = 1, name = "ram" },` new { id = 2, name = "ramesh" } };

var query = from stud in pairs
                where stud.id==1
                select stud;

var pairs = new [] { new { id = 1, name = "ram" }, new { id = 2, name = "ramesh" } };
var query = from stud in pairs
            where stud.id == 1
            select stud;

var query = from dynamic stud in pairs
               where stud.id == 1
               select stud;

public class Student
{
    public int Id { get; set; }
    public string Name { get; set; }
}

var students = new List<Student> {
      new Student { Id = 1, Name = "ram" },
      new Student { Id = 2, Name = "ramesh" }
    };