Bonding

Which of the following scientific claims about the bond in the molecular compound HF is most likely to be true?

• There is a partial negative charge on the H atom.

• Electrons are shared equally between the H and F atoms.

• The bond is extremely weak.

• The bond is highly polar.

Tags

NGSS.HS-PS1-1

Two pure elements react to form a compound. One element is an alkali metal, X, and the other element is a halogen, Z. Which of the following is the most valid scientific claim that can be made about the compound?

• It has the formula XZ₂

• It does not dissolve in water.

• It contains ionic bonds.

• It contains covalent bonds.

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

NGSS.HS-PS1-3

The elements C and Se have the same electronegativity value, 2.55. Which of the following claims about the compound that forms from C and Se is most likely to be true?

• The carbon-to-selenium bond is unstable.

• The carbon-to-selenium bond is nonpolar covalent.

• The compound has the empirical formula CSe.

• A molecule of the compound will have a partial negative charge on the carbon atom.

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Has a central atom with less than an octet of electrons

• H₂O

• NH₃

• BH₃

• CH₄

• SiH₄

Has two lone pairs of electrons

• H₂O

• NH₃

• BH₃

• CH₄

• SiH₄

Which of the following Lewis diagrams best represents the bonding in the N₂O molecule, considering formal charges?

• 
• 
• 
• 

Tags

NGSS.HS-PS1-2

Of the following compounds, which is the most ionic?

• SiCl₄

• BrCl

• PCl₃

• Cl₂O

• CaCl₂

Tags

NGSS.HS-PS1-3

Of the following molecules, which has the largest dipole moment?

• CO

• CO₂

• O₂

• HF

• F₂

Of the following single bonds, which is the LEAST polar?

• N-H

• H-F

• O-F

• I-F

The electron-dot structure (Lewis structure) for which of the following molecules would have two unshared pairs of electrons on the central atom?

• H₂S

• NH₃

• CH₄

• HCN

• CO₂