How many electrons are in an ion of calcium (Ca2+)?
A. 2
B. 18
C. 0
D. 22

Compare and contrast physical changes with chemical changes.

The formation of a solid, also known as a is an indication of a chemical change. precipitate particulate particle powder

Which of the following is most likely true about water in chemical systems? a) water dissolves nonpolar ionic compounds. b) water dissociates ionic compounds. c) water dissociates covalent molecules. d) water dissolves nonpolar covalent substances.