Dissociation of Water Molecules

Part A

What name is given to this molecule?

	water
	hydroxide ion
	methane
	glucose
	hydronium ion

Correct

A water molecule that gains a hydrogen becomes a hydronium ion.

Part B

How did this molecule form?

	A water molecule gained an hydrogen ion from another water molecule.
	Two water molecules bonded.
	A water molecule split in half.
	A hydrogen molecule bonded with an OH- molecule.
	Evaporation.

Correct

This molecule was formed by the transfer of a hydrogen ion from one water molecule to another.

Part C

What name is given to this molecule?

	DNA
	hydronium ion
	water
	glucose
	hydroxide ion

Correct

A water molecule that loses a hydrogen ion is referred to as a hydroxide ion.

Part D

This animation illustrates the _____ of water.

To view the animation, click here. Then click on the image to start the animation.

	surface tension
	cohesion
	dissociation
	adhesion
	specific heat

Correct

The transfer of a hydrogen atom from one water molecule to another is referred to as dissociation.

Part E

Which of these is the correct equation for the dissociation of water?

	H2O + H2O+<==> H2O + OH-
	H2O + H2O <==> H3O+ + OH-
	H2O <==> H+ + OH-
	H+<==> H2O + H2O+
	H2O + OH-<==> H2O+

Correct

This is the correct equation for the dissociation of water molecules.

Part F

What is the charge on a hydronium ion?

	2+
	0
	1+
	1-
	2-

Correct

The formation of hydronium results in the gain of 1 more proton than electron.

Part G

What is the charge on a hydroxide ion?

	1+
	2-
	1-
	2+
	0

Correct

A hydroxide ion is formed when a water molecule loses a hydrogen ion.

Part H

About _____ molecules in a glass of water are dissociated.

	1 in 1,000,000,000
	1 in 500,000,000
	1 in 1,000,000
	1 in 5,000,000
	1 in 2

Correct

One in half a billion.