Part A: Key: Naming and Writing Covalent Compounds

In a chemistry class, Josue and Michael are learning about covalent compounds. They discover that covalent compounds are named by adding _______ to the element names.

• prefixes

• suffixes

• numbers

• symbols

Answer explanation

Covalent compounds are named using prefixes to indicate the number of atoms of each element present. For example, 'di-' for two and 'tri-' for three. Thus, the correct answer is 'prefixes'.

Hailey and Jeancarlos are discussing the types of elements that form covalent compounds. Covalent Compounds consist of _______.

• nonmetals

• metals

• metalloids

• noble gases

Answer explanation

Covalent compounds are formed when nonmetals share electrons. This characteristic distinguishes them from metals and metalloids, which typically form ionic or metallic bonds.

A prefix is added to the name of the _______ element only if it has a subscript.

• first

• second

• third

• fourth

Answer explanation

A prefix is added to the name of the first element only if it has a subscript. This is a convention in naming compounds, where the first element's name is modified to indicate the number of atoms present.

Andrea and Zoey are learning chemistry. Andrea explains that a prefix is always added to the name of the _______ element in the formula, and the second element will end in 'ide'.

Answer explanation

In chemical nomenclature, a prefix is always added to the name of the first element in the formula, while the second element's name ends in 'ide'. Therefore, the correct answer is 'first', not 'second'.

Yamilet and Treasure are learning about covalent compounds in their chemistry class. They discovered that the names of covalent compounds contain _______ that indicate the number of atoms that are present in each element in the covalent compound.

• prefixes

• suffixes

• symbols

• numbers

Answer explanation

The names of covalent compounds use prefixes to indicate the number of atoms of each element. For example, 'di-' means two, 'tri-' means three, etc. This is why 'prefixes' is the correct answer.

When Tony and Gustavo are writing covalent compounds for their chemistry project, they find that the _______ are determined directly from the prefixes in the name.

• subscripts

• coefficients

• charges

• masses

Answer explanation

In covalent compounds, the prefixes in the name indicate the number of atoms of each element. These numbers are represented as subscripts in the chemical formula, making 'subscripts' the correct choice.

Tags

NGSS.MS-PS1-1

Elsie and Michael are in a science class learning about different chemical compounds. Their teacher asks them, "What is the chemical name for the compound with the formula CH4?"

• Carbon tetrahydride (methane)

• Carbon dioxide

• Methanol

• Ethane

Answer explanation

The compound with the formula CH4 is known as carbon tetrahydride, commonly referred to as methane. It consists of one carbon atom bonded to four hydrogen atoms, making it the correct choice.

Tags

NGSS.MS-PS1-1

Yamilet and Charity are working on a chemistry project where they need to identify the chemical name for the compound with the formula Si2Br6. What is the chemical name for this compound?

• disilicon hexabromide

• silicon bromide

• disilicon tribromide

• silicon hexabromide

Answer explanation

The formula Si2Br6 indicates two silicon (Si) atoms and six bromine (Br) atoms. The correct IUPAC name is disilicon hexabromide, reflecting the number of each type of atom in the compound.

Tags

NGSS.MS-PS1-1

Lliana and Coral are working on a science project about different gases. They come across a compound with the formula NF3. What is the chemical name for this compound?

• nitrogen trifluoride

• nitrogen trichloride

• ammonia

• nitrogen dioxide

Answer explanation

The compound NF3 is named nitrogen trifluoride, as it consists of one nitrogen atom and three fluorine atoms. The other options do not match the formula or the correct naming conventions.

Tags

NGSS.MS-PS1-1

During a chemistry class, Josue and Elsie were discussing the chemical name for the compound with the formula HI. What is the chemical name for this compound?

• hydrogen iodide

• hydrogen chloride

• hydrogen bromide

• hydrogen fluoride

Answer explanation

The compound with the formula HI is called hydrogen iodide. The other options refer to different compounds: hydrogen chloride (HCl), hydrogen bromide (HBr), and hydrogen fluoride (HF).