Covalent bond

1.What attractions hold two atoms in a molecule together?

• attraction between ions with opposite charges

• attraction between the nuclei of the atoms and shared electrons

• attraction between each nucleus and the electrons of the other atom

• attraction between the molecule and other molecules

Tags

NGSS.HS-PS1-4

2.What determines whether a molecule is polar?

• a.type of atoms and shape of molecule

• mass of atoms and number of valence electrons

• type and mass of atoms

• ionization energy and number of covalent bonds

3.Why does water have a much higher boiling point than methane?

• a.Methane molecules are more polar, so its molecules have stronger attractive forces.

• b.Partial charges on the polar water molecules increase attractive forces between molecules.

• c.A water molecule has much more mass than a methane molecule, so water has a higher boiling point.

• d.Water has a higher boiling point because its molecules do not contain carbon atoms.

is a chemical bond in which two atoms share a pair of valence electrons.

• covalent bond

• Ionic bond

• Metalic bond

When atoms form a polar covalent bond, the atom with the greater attraction for electrons has a partial positive charge. The other atom has a partial negative charge.

• True

• False

•A covalent bond in which electrons are shared equally is called a polar covalent bond.

• True

• False

In a carbon dioxide (CO2) molecule, the polar bonds between the carbon atom and the oxygen atoms cancel out because the molecule is linear.

• True

• False

In a water (H2O) molecule, the polar bonds between the oxygen atom and the hydrogen atoms do not cancel out because the molecule is bent.

• True

• False

Attractions between non-polar molecules are stronger than attractions between polar molecules.

• True

• False

• A

• B

• C

• D