Different Hashcode For Object Before And After Serialization

I am studying Serialization from the SCJP 6 Kathy Sierra book. I came across this code snippet.

public class Cat implements Serializable {
public static void main(String[] args) {
Cat c = new Cat();
try {
FileOutputStream fs = new FileOutputStream("testSer.ser");
ObjectOutputStream os = new ObjectOutputStream(fs);
os.writeObject(c);

[code]....

The output is as follows.

files.Cat@4d43691d
files.Cat@7f39ebdb

1) Why are the two hashcodes different?

2) Serialization is supposed to make and identical copy of any object and all its instance variables. So, if the hashcodes are different, are these objects located in different locations in heap?