Energy is released when a new bonds form.
An isotope has the same number of <em>protons</em> but a different number of <em>elec</em><em>tro</em><em>n</em><em>s</em><em> </em>than others atom of the same element
A and d is physical, b and c is chemical
Answer:
The answers to your questions are below
Explanation:
Physical change is when matter changes its form but is still the same substance.
Chemical change is when matter changes its composition.
iron and oxygen from rust It's a chemical change because iron and oxygen form a new compound different from the reactants.
iron is denser brightly when ignited
. This is a chemical property because iron reacts with oxygen.
oil and water do not mix
it's a physical change, oil and water are in touch but they do not react.
mercury melts at -39°C it's a physical property because mercury changes from solid to liquid but it still is mercury.
This shows what it is and it's always true
