If two types of matter are combined and energy is given off, what type of change is likely to have occurred? chemical change

physical change

particle change


shape change

In a water molecule, hydrogen and oxygen are held together by a(an) bond. a) double covalent b) ionic c) nonpolar covalent d) hydrogen e) polar covalent

What characteristics does a earthquake have

Achemist who studies water samples did a demonstration of how to test for lead in water. she added a clear solution of potassium iodide to a clear solution of lead nitrate. then a yellow swirling solid formed in the liquid. what is most likely true about the yellow solid?