Chemistry Unit 9 Test

Which of the following substances would you expect to have the highest melting point

• carbon dioxide (CO₂)

• sulfur dioxide (SO₂)

• hydrogen peroxide (H₂O₂)

• aluminum oxide (Al₂O₃)

Tags

NGSS.HS-PS1-3

When two atoms share three pairs of electrons with one another, what type of bond do they form?

• triple ionic bond

• triple covalent bond

• double ionic bond

• double covalent bond

Tags

NGSS.HS-PS1-1

What happens to electrons during covalent bonding?

• They are given up by atoms.

• They are taken in by atoms.

• They are shared between atoms.

• They are transferred between atoms.

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NGSS.HS-PS1-1

Which of the following pairs of elements are most likely to form polar covalent bonds. (select all correct answers)

• magnesium and nitrogen

• silicon and oxygen

• silicon and phosphorus

• sulfur and chlorine

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

What is the largest difference in electronegativity between two atoms that form a nonpolar covalent bond?

• 0.4

• 2.78

• 0.0

• 1.7

Hydrogen and oxygen are gasses at room temperature because they have ____________________, while water is a liquid at room temperature because it has _____________________.

• hydrogen bonding, London dispersion forces

• London dispersion forces, hydrogen bonding

• strong intermolecular forces, no intermolecular forces

• hydrogen bonding, dipole-dipole forces

Hydrogen bonding most likely occurs in which compound?

• NH₃

• LiH

• CH₄

• SF₂

Tags

NGSS.HS-PS1-3

Which element would be likely to form a strong intermolecular bond with hydrogen?

• phosphorus

• carbon

• oxygen

• aluminum

Tags

NGSS.HS-PS1-3

Which best explains the surface tension of water?

• Density is greater at the surface, so there are more water molecules are there and the hydrogen bonding works better.

• Intermolecular forces are greater at the surface.

• Pressure increases with depth, so the hydrogen bonding is only strong enough to have surface tension at the top.

• Surface molecules of water are attracted only downward and sideways by hydrogen bonding.

Which statement best describes the dipoles that cause London dispersion forces?

• The dipoles are caused by a difference in electronegativity.

• The dipoles are permanent separations of charges.

• The dipoles are instantaneous and temporary.

• The dipoles contain a hydrogen atom.