Shape and Weight
make that clay into a ball and you weigh it on a scale.
It might weigh something like 100g.
Next, you take that same clay and shape it into a snake.
If you weigh it again, it will still be 100g.
It's like if you had a clay and small it into pieces.
The pieces might look different, but if you put them all together again, the weight would be the same as the whole clay.
↓
So, no matter how you shape the clay, the weight won't change.