Organic Chemistry Lab 1 Study guides, Class notes & Summaries

Lab 1: Isolation of essential oils Why did we use steam distillation? - Steam distillation is used for temperaturesensitive compound which is immiscible in water. - In order to boil, the vapor pressure of liquid = vapor pressure of atm. Water and oil are immiscible. Therefore, they both contribute to vapor pressure. As a result, the mixture will start boiling at lower temperature than each of the compound does => we don't want to heat the mixture at the compound boiling point, it...

How should BP of a liquid be reported?As a boiling range How does temperature affect the vapor pressure of a liquid?As temperature increases, vapor pressure increases Suppose you will be distilling 50 mL of an impure liquid. What size of distillation flask(s) should you use?100 and 150 mL What is the purpose of using boiling stones?To relieve minor hot spots on the distillation flask and prevent vigorous eruption of bubbles (bumping) What should be the temperature difference in the liq...

The three principal reasons for determining the mp range of a solid (For what reason(s) would someone be interested in determining the melting point (mp) range of a compound 1) Determination of purity 2) Establishing an unknown solid's identity 3)Reporting new physical property data on a compound never before isolated/made Purpose of this experiment To experimentally determine the effect of impurity (urea) on the mp range of a pure substance Draw trans-cinnamic acid Draw urea

Physical properties can be useful toDetermine structure Determine purity of substance If not pure, determine how to separate contaminating substances from a compound What can you get from melting point?Identify and purity of an organic solid. Define melting pointWhen the temperature at which the solid and liquid states are in equilibrium. What's the range at which most organic substances melt?50 - 250 C What's the range at which inorganic substances usually melt?300 - 1500 C What subs...