Chemical Bonds and Chemical Bonds and ReactionsReactions

Two kinds of bonds Two kinds of bonds

• Ionic

• Covalent

• Chemical Bonds and Reactions

Ionic bonds Ionic bonds

• Ions of opposite charge join together

• Na+ and Cl- = NaCl Chemical Bonds and Reactions

Covalent Bonds Covalent Bonds

• Electrons are shared when elements join together

• water - H20 Chemical Bonds and Reactions

Chemical Reactions Chemical Reactions

• Reactants are changed into a new substance, products.

• HCl + NaOH --> NaCl +H2O Chemical Bonds and ReactionsEnergy Changes

Endothermic reactions Endothermic reactions

- energy is used to make something Chemical Bonds and Reactions.

Exothermic reaction –Exothermic reaction –

- energy is given off.

-MIXTURESMIXTURES

- Combination of substances that are not chemically bonded For example sand and water, or air MIXTURES

Solution Solution

• a uniform mixture of two or more substance.

MIXTURESMIXTURES

• 2 parts of a mixture

• Solute - the dissolved substance

• Solvent - the dissolving substance

MIXTURESMIXTURES

• Kool-aid

• What is needed to make it?

• What is the solvent and what is the solute?

Common Types of SolutionsCommon Types of Solutions

• Gas-gas air

• Liquid-gas moist air

• Gas-liquid soda water

• Liquid-liquid vinegar

Common Types of SolutionsCommon Types of Solutions

• Solid-liquid brine

• Solid-solid sterling sliver

• Water H2O

Water H2OWater H2O

• Essential part of living things

• 65-95 % the human body

• You can live 60 days without food

• you can only live 6 days without water.

Water - H2OWater - H2O

• Two Hydrogen and One oxygen

Covalent Bond Covalent Bond

• Water is the universal solvent.

• Hydrogen bond is unique

• Makes blood circulation possible

Acids, Bases, and SaltsAcids, Bases, and Salts

• Acids - compounds that release hydrogen ions (H+)

• Bases - compounds that release hydroxide ions (OH-)

Acids, Bases, and SaltsAcids, Bases, and Salts

– Salts • compounds that release ions other than hydrogen

or hydroxide ions • Neither a acid nor a base.

– Salts dissolve in water are • electrolytes because they conduct an electrical

current • Sports drinks are mixtures of electrolytes that are

used to replace salts excreted in sweat when a person exercises. pH

ScaleScale

• A standard measurement of the concentration of hydrogen ions (H+) in a solution.

ScaleScale

• 0 to 14 pH Scale

• Basic 13 bleach

• 11 ammonia

• 9 baking soda

ScaleScale

• 8 egg whites pH Scale

• Neutral

• 7.5 Blood

• 7 Water pH Scale

• Acid 5 coffee

• 4 tomato juice

• 3 vinegar

• 2 lemon juice

• .5 battery acid