Water

What happens when covalent compounds dissolve in water?

Covalent compounds do not separate into individual ions, because they are not ions. Instead, they separate into individual molecules. They do not dissociate because the covalent bonds do not separate in water. Instead, the molecules are separated from eachother but the individual molecules remain intact and stable.

Where is water found?

Cytosol in cytoplasm, intercellular fluids, bloodstream

Water is Polar

The Oxygen, because of its bigger nucleus and more protons, tends to have a more powerful attraction for electrons when shared with 2 Hydrogen. As a result, the Oxygen tends to be partially negative and the Hydrogen is partially positive.

Hydrogen Bonds

The attraction between one partially positively charged Hydrogen in a molecule and one partially negatively charged Oxygen of another molecule. These bonds are not strong.

pH

The number of Hydrogen or hydronium ions in a solution.

Neutral Medium

pH 7 The amount of Hydrogen Ions, or hydronium ions, is equal to the amount of Hydroxide Ions.

Acidic Medium

pH <7 The lower the number, the more acidic the substance is, meaning that it loses more Hydrogen Ions in water. The Hydrogen Ions are attracted to Water because of its polarity and creates Hydronium ions. It also is attracted to Hydroxide Ions, which then bonds to create Water. This decreases the amount of Hydroxide Ions. The result is an Acidic Solution

Basic Medium

pH >7 The pH is more than 7. This means that the substance adds Hydroxide Ions when dissolved in a substance. The Hydroxide Ion concentration outweighs the Hydrogen Ion or Hydronium ion concentration. The Hydroxide Ion is attracted to Hydrogen Ions, creating water and reducing the amount of Hydrogen Ions or Hydronium Ions. The result is an Alkaline or Basic Solution.

Solution

A liquid mixture in which a solute is evenly distributed in a solvent.

Saturated Solution

A liquid mixture where the amount of solute is equal to the solvent.

Base

Any substance that increases the amount of Hydroxide Ions to a solution.

Acid

Any substance that separates into Hydrogen Ions when dissolved in water.

Hydrogen Ion Acceptors

Bases

Water is Cohesive

Because of the polar bonds, leading to hydrogen bonds, water tends to stick to itself. One molecule of water can form up to 4 bonds. This allows for water to have surface area and form beads on a smooth surface.

Dissociation of Water

Because oxygen has such a strong pull for electrons, sometimes it takes Hydrogen's electron, creating a Hydrogen ion (Positive because one proton) This happens very rarely. 2 in every billion water molecules dissociate. Water molecules are constantly moving and the H and OH can rebond to create H2O.

Polar Covalent Bonds

Bonds in which the electrons are not equally shared. As a result, one end is partially positive and one end is partially negative. ex. OH ex. anything with O

Water

H2O

Water is less dense when frozen

Hydrogen bonds expand and become stable when energy is released and cause the water molecules to have a 3D structure. They do not move much in these structures and have a lot of space between molecules, thus making it less dense. When water is in liquid form, there is much more energy and hydrogen bonds are constantly breaking and reforming.

Suspension

Mixture of water and non dissolved materials.

Hydrophillic

Polar or Ionic Compounds are hydrophilic, meaning they dissolve in water.

Dissociation

Separation of Ions

Hydrophobic

Substances that are non polar or fats do not bond with water, or dissolve.

Non Polar Covalent Bonds

The strongest type of bond. This bond does not break when dissolved in water. This is a bond in which electrons are shared equally. ex. CH4 Ex. any atom bonded to itself

Solute

The substance being dissolved.

Solvent

The substance that is dissolving the solute.

Hydronium Ion

This forms when water dissociates. The Hydrogen Ion is attracted to the polar water molecule. The partially negative Oxygen binds to the Hydrogen, creating a positive hydronium ion.

Water has a high heat capacity

This is a result of multiple hydrogen bonds. Large amounts of energy is needed to make the molecules move faster, which raises the temperature. This is why water is essential to life. When cells release heat, water absorbs the heat so that it regulates body temperature.

Neutral Solution

This means that the dissociation of water always results in an equal amount of positively charged hydronium ions and negatively charged hydroxide ions.

Water is Adhesive

Water molecules are attracted to other polar substances. This causes water to have a meniscus because it dips in the middle. The water sticks to the side of the glass. This causes water to rise against gravity in a glass. This also creates a capillary action in plants. The adhesion causes water to rise up while cohesion causes the water to stay together.

Water can dissolve substances

Water's polar bonds create a partially positive hydrogen and partially negative oxygen. This creates an attraction between polar molecules and ionic compounds.

What happens when ionic compounds dissolve in water?

Water's polarity causes an attraction between negative and positive ions. The partially positive Hydrogen is attracted to the negative nonmetal and surrounds it, causing it to dissociate. The ionic bonds separate into individual ions.

Dissolving

When water or another molecule can surround charged particles like ions or polar molecules and cause them to separate.

pH scale

pH goes by increments of 10. The H ion concentration starts at the 0 (pH 1) and ends at -14(pH 14). The H ion concentration and the OH- ion concentration add up to -14. The exponent of the Hydrogen Ion is the pH number.

Concentration

the quantity of a substance in a given volume.