Losing electrons and forming positive ions
Answer:
A. a system that can be affected by the outside environment, by an exchange of matter or energy
Answer:
When a physical change occurs, the arrangement of particles within the substance may change, but the atoms in the molecules remain bonded together.
Explanation:
Srry didn't see this till now, hope u got it right :)
I think it's Sodium Sulfide, because Na2S contains one Sodium and two Sulfur. Plus Sulfide<span> is used to describe any of three types of chemical compounds that contain sulfur.</span>