You can treat a polyatomic ion as an element when balancing equations. The following example involves the polyatomic ion NO3-. Notice that the entire polyatomic ion is placed in parentheses and given its own subscript.
2Al(s) + 3Mg(NO3)2(aq) --> 2Al(NO3)3(aq) + 3Mg(s)
Radium is a chemical element; a compound has a minimum of two chemical elements.
Radium is a chemical element, not a compound.
How does a subscript affect the element just before it?
Right and down the symbol of a chemical element.
A metal is a chemical element not a compound.
Magnesium is a chemical element, not a compound.
Copper is a chemical element. It can be a compound but copper is usually known as a chemical element.
Francium is a GROUP 1 metallic ELEMENT. It is a the bottom of Group 1 . Its partner elements in the Group are, lithium, sodium, potassium, rubidium, & caesium. They all react with water with increasing violence. to the point of explositivity. Francium is also Radio-Active, so you will not find it in any school lab. or even industrial labs. It is probably kept in a very special nuclear research lab. under very controlled conditions. It was discovered by Marie Curie, in France, hence its name.
Radium is a chemical element; a compound has a minimum of two chemical elements.
Radium is a chemical element, not a compound.
Silver is a metalic chemical element.
How does a subscript affect the element just before it?
Sodium is a chemical element. Salt is a compound of sodium and chlorine.
Right and down the symbol of a chemical element.
Iodine is a chemical element; not a mixture, not a compound.
I2 is an Element. It is the chemical symbol for molecular iodine.
Potassium is a chemical element.