Polyatomic Nomenclature and Formula

What is a polyatomic ion?

• A clump of atoms with a charge

• A single atom with a charge

• A compound with no charge

• A group of elements with no charge

Answer explanation

A polyatomic ion, as the question asks, is indeed a clump of atoms with a charge. It's not a single atom with a charge, because that would be a monatomic ion. Likewise, it's not a group of elements or a compound without charge, as both these options lack the characteristic charge that defines a polyatomic ion.

What is the charge of Calcium?

• 1 minus (-1)

• 2 plus (+2)

• 2 minus (-2)

• 1 plus (+1)

Answer explanation

Calcium, a chemical element, is a part of the alkaline earth metals group. Its charge is determined by losing two electrons to achieve a stable electron configuration. So, the correct charge for Calcium is 2 plus (+2).

What is the charge of Nitrate?

• 1 minus (-1)

• 2 plus (+2)

• 2 minus (-2)

• 1 plus (+1)

Answer explanation

The charge of Nitrate is 1 minus (-1). In the options provided, only this answer correctly corresponds to the question. Nitrate is a polyatomic ion composed of one nitrogen atom and three oxygen atoms and carries a charge of -1, hence it is the correct choice.

What is the chemical formula for Calcium Nitrate?

• Ca(NO₃)₂

• CaNO₃

• Ca₂NO₃

• Ca₂(NO₃)₂

Answer explanation

The chemical formula for Calcium Nitrate is Ca(NO3)2. This is represented by the formula Ca(NO3)2, which signifies one atom of calcium (Ca) and two nitrate ions (NO3). The subscript '2' after the parenthesis indicates that there are two nitrate ions for each calcium ion in the compound.

What is the charge of Ammonium?

• 1 minus (-1)

• 2 plus (+2)

• 2 minus (-2)

• 1 plus (+1)

Answer explanation

The question asks about the charge of Ammonium. Ammonium is a polyatomic ion and it carries a charge of 1 plus (+1). This means that it has lost one electron, making it positively charged. Therefore, among the given options, '1 plus (+1)' is the correct answer.

What is the charge of Nitride?

• 1 minus (-1)

• 2 plus (+2)

• 3 minus (-3)

• 1 plus (+1)

Answer explanation

The charge of an ion is determined by the number of electrons compared to protons. Nitride is an ion formed from nitrogen and it has gained three electrons to have a full outer shell. This gives it a charge of 3 minus (-3). Therefore, the correct answer to the question 'What is the charge of Nitride?' is '3 minus (-3)'.

What is the chemical formula for Ammonium Nitride?

• (NH₄)₂N

• NH₄N

• NH₄NO₃

• NH₄(NO₃)₂

Answer explanation

The question asks for the chemical formula of Ammonium Nitride. The correct formula is (NH4)2N. This is because Ammonium is a polyatomic ion with the formula NH4+ and Nitride is a monatomic ion with the formula N3-. The subscript 2 on Ammonium indicates there are two NH4+ ions for every one N3- ion to balance the charges and yield a neutral compound.

What is the charge of Sodium?

• 1 minus (-1)

• 2 plus (+2)

• 2 minus (-2)

• 1 plus (+1)

Answer explanation

The question asks about the charge of Sodium. Sodium, a chemical element, always has a charge of 1 plus (+1). This is because it has one electron in its outermost shell which it loses to achieve a stable electron configuration, thereby acquiring a positive charge. Hence, the correct choice is '1 plus (+1)'

What is the charge of Carbonate?

• 1 minus (-1)

• 2 plus (+2)

• 2 minus (-2)

• 1 plus (+1)

Answer explanation

The question asks about the charge of Carbonate. Carbonate is a polyatomic ion with the formula CO₃ and carries a 2 minus (-2) charge. So, the correct choice is '2 minus (-2)'. The other options listed do not correctly represent the charge of Carbonate.

What is the chemical formula for Sodium Carbonate?

• Na₂CO₃

• NaCO₃

• Na₂(CO₃)2

• Na(CO₃)₂

Answer explanation

The chemical formula for Sodium Carbonate is indeed Na₂CO₃. Sodium Carbonate, known as soda ash or washing soda, is a sodium salt of carbonic acid. Its formula indicates it contains two atoms of sodium (Na), one of carbon (C), and three of oxygen (O). Thus, it correctly corresponds to the given answer.