The NH4 asked about is the amonium ion, and it's written NH4+ to indicate it has a positive charge (+1). It's a cation. Wikipedia has more information on this chemically â¦ significant polyatomic ion, and you'll find that a link to that post is provided below. + 7 others found this useful.
Gilbert is a town in Maricopa County, Arizona, United States, just southeast of Phoenix, within the Phoenix metropolitan area.
Pima County, where the City of Tucson is located, is the second largest count in Arizona. It grew 16.2% from 2000 (population 843,746) to 2010 (population 980,263), with a net growth of 37 people per day.