NGS Ch 10 - Section 2: Writing Formulas and Naming Compounds

What is a binary compound?

• A compound composed of three elements

• A compound with water attached

• A compound composed of just two elements

• A compound with a net charge of one

Answer explanation

A binary compound is a chemical compound made up of only two different elements. The prefix "bi-" means "two," which is the key to understanding this term. It doesn't matter how many atoms of each element are in the compound, as long as there are only two types of elements.

For example, water (H₂​O) is a binary compound because it's composed of hydrogen (H) and oxygen (O).

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Examples of Binary Compounds 🧪

• Sodium chloride (NaCl) is a binary ionic compound made of sodium (Na) and chlorine (Cl).

• Carbon dioxide (CO₂​) is a binary covalent compound made of carbon (C) and oxygen (O).

A compound with a net charge is called an ion, not a compound. An example of a polyatomic ion with a charge of +1 is the ammonium ion (NH₄⁺​), which is composed of nitrogen and hydrogen but has a net charge.

Tags

NGSS.MS-PS1-1

What is a hydrate?

• A compound with water chemically attached to its ions

• A compound composed of two metals

• A compound with no water

• A compound with a net charge of zero

What does the prefix 'poly' in polyatomic mean?

• One

• Two

• Many

• None

What is the oxidation number?

• A positive or negative number indicating electron gain, loss, or sharing

• The number of protons in an atom

• The number of neutrons in an atom

• The atomic mass of an element

Which method is used to ensure the sum of oxidation numbers in a formula is zero?

• The crisscross method

• The division method

• The subtraction method

• The addition method

What is the root of the name for chlorine when naming compounds?

• Ch-

• Chlo-

• Chlor-

• Chl-

How do you name a covalent compound with two nitrogen atoms and one oxygen atom?

• Nitrogen dioxide

• Dinitrogen monoxide

• Nitrogen oxide

• Mononitrogen dioxide

What is the correct name for the compound BaF2?

• Barium Fluoride

• Barium Fluorine

• Barium Difluoride

• Barium Monofluoride

Which of the following is a polyatomic ion?

• NH4+

• Cl-

• O2-

• Na+

What is the first step in writing formulas for compounds?

• Add subscripts to balance the charge

• Write the symbol of the element with the positive oxidation number

• Write the symbol of the element with the negative oxidation number

• Determine the root of the second element