Which ion will combine with sulfide in a 2:1 ratio, and why? a). chloride

b). magnesium ion

c). ammonium

d). nitrate

Describe what happens to the molecules as water goes from ice to liquid to vapor. be sure to explain what happens to the temperature during the phase changes.

What is the most common reason for matter changing its state?

Where are the noble gases located in the periodic table? a. in the center b. on the left side c. in the upper right corner d. on the far right side