1 significant figure, because there is no decimal after the zero the zero doesn't count.
In order to balance this equation you need to count each element and how many of the individual elements are in the equation.
_H2+N2=2 NH3
You multiply the 2 (Which is the coefficient) by the 3 (which is the subscript) This would equal 6 which indicated there are 6 hydrogen atoms on the right side so the left side should also have 6 hydrogen atoms
The missing coefficient on the left side must multiple the 2 to become 6 hydrogen
Answer=3
So in a chemical change, the product would loses its properties, would form new products and would not be easily reversed.
In a physical change, the products WILL NOT lose any of their properties, WILL NOT form any new products and WILL be easily reversed.
Talking about Water turning to ice I would say it’s all about physical change and not chemical change.
But I would suggest you to either make a research about it or ask your teacher :))
If you hit something it hurts in an equal amount that you hurt it
