Lab 6

 Reactions are complex
 Gases, solids and liquids all react differently
 What you will be learning today are the basics only
 Always work with balanced reactions
 Balanced reactions provide us with molar ratios of reagents to products

 We cannot make direct comparisons in chemistry using concentration or mass we use moles instead.
 A mole is 6.022 x 10 23 of anything.
 This concept is similar to that of a dozen.
 We will be using the concept of a dozen today since 6.022 x 10 23 are too many items to count out.

 A limiting reagent is the reagent you run out of first in a reaction.
 The reagent that is in excess is called, excess reagent.
 You must determine the limiting reagent of a reaction before you can determine the theoretical yield of product.
 You will be limited by mass and number of items in some of your questions today to demonstrate this point.

 Theoretical yield is calculated to predict how much product can be produced based on the limiting reagent calculation.
 You will use your predicted masses
(theoretical values) to do your ratio calculations today.
 After the theoretical yield is established, and the actual yield obtained, one can calculate percent yield.

 Each balance auto-calibrates
 Carefully open a door and make sure the basket is fully hinged
 Place a blue weigh boat on the basket
 Close the door completely and without slamming it
 Tare the boat
 Add the hardware and close the door carefully
 Record the mass to the closest 0.1 mg (0.0001 g)
 Remove your hardware, close the door(s) carefully and push the zero button

 Collect the required pieces of hardware from their containers.
 Place these in a white plastic weigh boat.
 The hardware may contain some oil. Wear gloves if you don’t want oil on your hands.
 Use the plastic weigh boat to carry your hardware. It does not fit in the balance.
 Use a blue plastic weigh boat in the balance to weigh your hardware.
 Small pieces get lost easily. Please keep track of ALL your equipment.

 Read the required reading sections in your textbook and lab manual as you prepare for Lab 7.
 Go through the significant figure molar mass tutorial in Blackboard before attempting the prelab questions.
 Use the periodic table in your lab manual.
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Complete and submit your pre-lab questions by the deadline.
Study for the next quiz.
Submit your Lab 6 Report at the start of next week’s lab.