Unit 5 - Nomenclature Test Review

Which of the following is the correct formula for Calcium sulfate?

• CaSO4

• Ca2SO4

• Ca(SO4)2

• CaS

Answer explanation

The correct formula for Calcium sulfate is CaSO4. This indicates one calcium (Ca) atom and one sulfate (SO4) group, making it the simplest and correct representation of the compound.

The polyatomic ion Nitrate is correctly written as:

• NO3-

• NO2-

• N2O3

• N2O4-

Answer explanation

The nitrate ion is represented as NO3-. It consists of one nitrogen atom and three oxygen atoms, carrying a negative charge. The other options do not correctly represent the nitrate ion.

NO3- is the polyatomic ion:

• Nitrate

• Nitrite

• Nitride

• Ammonium

Answer explanation

NO3- is the chemical formula for the nitrate ion, which is a polyatomic ion consisting of one nitrogen atom and three oxygen atoms. The other options refer to different ions: nitrite (NO2-), nitride (N3-), and ammonium (NH4+).

Which of the following is a positive polyatomic ion?

• Phosphate

• Ammonium

• Sulfate

• Carbonate

Answer explanation

Ammonium (NH4+) is a positive polyatomic ion, while phosphate (PO4^3-), sulfate (SO4^2-), and carbonate (CO3^2-) are all negative ions. Therefore, the correct answer is ammonium.

The ion form of the non-metal Chlorine is called:

• Chlorite

• Chloride

• Hypochlorite

• Perchlorate

Answer explanation

The ion form of Chlorine is called Chloride (Cl-). Chlorite, Hypochlorite, and Perchlorate refer to different chlorine compounds with varying oxidation states, not the simple ion form.

Which of the following is the correct name for Fe2O3?

• Iron (II) Oxide

• Iron (III) Oxide

• Ferric Acid

• Iron Hydroxide

Answer explanation

Fe2O3 is composed of iron in the +3 oxidation state, hence it is correctly named Iron (III) Oxide. The other options either refer to different compounds or incorrect oxidation states.

Tags

NGSS.HS-PS1-2

How many atoms, total, are in the compound Ethanol, C2H5OH?

• 6

• 8

• 9

• 7

Answer explanation

Ethanol (C2H5OH) contains 2 carbon (C) atoms, 6 hydrogen (H) atoms, and 1 oxygen (O) atom. Adding these gives a total of 2 + 6 + 1 = 9 atoms, making the correct answer 9.

Tags

NGSS.MS-PS1-1

Which is the correct formula for magnesium chloride?

• MgCl

• Mg2Cl

• MgCl2

• MgCl3

Answer explanation

The correct formula for magnesium chloride is MgCl2. Magnesium has a +2 charge and each chloride ion has a -1 charge, requiring two chloride ions to balance the charge of one magnesium ion.

Tags

NGSS.MS-PS1-1

Which of the following represent the ions NO3, NO2, NO, in this order?

• Nitrate, Nitrite, Nitride

• Nitrate, Nitride, Nitrite

• Nitrite, Nitrate, Nitride

• Nitrate, Nitrite, Oxide

Answer explanation

The correct order for the ions is Nitrate (NO3), Nitrite (NO2), and Nitride (NO). Thus, the answer is 'Nitrate, Nitrite, Nitride', which matches the first choice.

Ionic compounds are typically formed between:

• two or more metals

• a metal and a non-metal

• two or more non-metals

• a metal and a polyatomic ion

Answer explanation

Ionic compounds are formed when a metal donates electrons to a non-metal, resulting in the formation of positive and negative ions that attract each other. Thus, the correct answer is a metal and a non-metal.