please finish result section. Make sure you test at least 2 plastics if you have access to samples for them.

Lab 3: Intro Chemistry &161 Spring 2021 to Plastics General Chemistry with Lab 1 Duldulao Green River College – Updated 4/16/2021 Page 1 of 7 Name Lab 3: Introduction to Plastics Prelab 3 ( 10 pts tota l) due in Canvas Tuesday 4/20 Lab 3 Report (35 pts total , including prelab ) due in Canvas Tuesday 4/ 27 Prelab Instructions: 1. Read this hando ut and Writing Lab Reports before starting. 2. Write the prelab writeup in your lab notebook in pen. (5 pts) a. Create a Table of Contents at the beginning of your lab notebook . The Table of Contents should have your name, class (CHEM& 161), and quarter (Spring 2021) towards the top. In the main part of the table of contents, include lab #, title of lab, and page # for the first page where this lab starts. b. Complete the Header Information at the top of the first page that covers this lab . Add page numbering to the top right corner of your lab notebook pages. c. I. Introduction : Write this in your own words. Cop y Figure 1 , and Table 1 (just the codes and polymer names) into this section of your lab notebook. (3 pts) d. II. Procedure : Write this in your own words; do not copy this handout verbatim . (2 pts) e. III. Results: Start this section by labeling it, followed by a space for observations. Also write an empty Table 2 that takes up an entire page of the lab notebook, ready to be filled in with informati on about your collected plastic samples. 3. Complete the Prelab 3 question sheet (QS) on the last page(s) of this handout. (5 pts) 4. Submit the Prelab 3 QS and prelab writeup from your lab notebook as a pdf file in the Prelab 3 assignment page on Canvas by the prelab due date. Lab report instructions (everything in your lab notebook written in pen!) : 1. Fill out the Results section in your lab notebook, following the directions in the Results section of this handout. 2. Create an Analysis section in your lab notebook, immediately after the Results section. Answer the analysis questions from the lab handout in your lab notebook. 3. Submit your Results and Analysis sections of your lab notebook as a pdf file in the Lab 3 Report assignment page on Canvas by the lab report due date. You do not need to resubmit the question sheet or prelab writeup, unless you wrote anything new on those page s that was not previously submitted. Lab 3: Intro Chemistry &161 Spring 2021 to Plastics General Chemistry with Lab 1 Duldulao Green River College – Updated 4/16/2021 Page 2 of 7 INTRODUCTION Plastics are polymers , which are large molecules made up of long sequences of smaller units called monomers . Many polymers are found in nature, such as rubber. Another example in nature is proteins, which are made of amino acids. Proteins have many purposes in organisms, such as muscle development, catalysts in food digestion and other biochemical reactions, and immune system support. Synthetic (artificial) polymers also exist, and are commonly derived from fossil fuels and petroleum products. Plastics are types of synthetic polymers. A relatively new field of polymers is bioplastics, derived from biologic al sources such as corn or algae. The basic structure of a polymer is a long chain of covalently -bonded atoms called the backbone , usually made of carbon. Attached to the backbone, often in a regular pattern, are side groups of atoms. The simplest side group is a hydrogen atom, as found in polyethylene (Figure 1). The process of linking monomers together to form the polymer is called polymerization , with the repeating structural pattern observed in the polymer being called the repeating unit . The physical and chemical properties of a polymer depend on the monomer that is incorporated into the polymer. Many of the differences in properties of plastics can be observed or tested: density, hardness, bounciness, transmission of polarized light, absorbance of infrared light, glass transition temperature (a plastic is brittle b elow this temperature, and much more malleable above this temperature) and melting temperature are just some of these measured properties. These properties can be modified by techniques such as adding plasticizers and heating the plastic in a particular w ay. New plastics are made by combining different monomers in new ways to obtain the desired properties. Because of the varying properties of plastics, different plastics commonly have different uses in everyday life (Table 1). Different plastics have different properties, so they are used t o make different products. Once the products are no longer useful, they may be recycled or discarded. Practically, p lastic recycling only happens if it ’s easily accomplished and profitable. The first step in this process is to identify and sort plast ics by polymer type. Contaminants and impurities reduce the quality of the recycled plastic, and may prevent them from being recycled at all. The S ociety of the Plasti cs Industry, Inc., introduced a resin identification coding (RIC) system in 1988 at t he urging of recyclers around the country. Many states in the US require products to include this code to Figure 1. Structure of polyethylene (PE) . The structure of the repeating unit is shown in the square brackets at right. The monomer and the repeating unit contain the same number of atoms of each element. Lab 3: Intro Chemistry &161 Spring 2021 to Plastics General Chemistry with Lab 1 Duldulao Green River College – Updated 4/16/2021 Page 3 of 7 facilitate recycling. These codes are often found on the bottom of plastic items, characterized by a number inside a triangle made out o f arrows (Table 1). This lab will i ntroduce the collection of samples to be studied in a future experiment, proper use of a lab notebook , including typical conventions such as writing in pen and recording all observations, both quantitative (numerical) and qualitative (descriptive) . Table 1. Common Plastics and Their Uses. Resin ID Code (RIC) Polymer Name Chemical Structure (monomer) Description/ Common Products PET or PETE (Polyethylene terephthalate) Clear, tough plastic. Fizzy drink bottles, oven -ready meal trays and water bottles HDPE (High - density polyethylene) (linear) Stiff plastic. Milk and detergent bottles, yogurt and margarine tubs, cereal box liners and grocery, trash and retail bags PVC (Polyvinyl chloride) Rigid or flexible. Plastic food wrap, vegetable oil bottles , loose -leaf binders and plastic pipes LDPE (Low -density polyethylene) (highly branched) Ductile plastic. Dry cleaning bags, produce bags, trash can liners, bread bags, frozen food bags and squeezable bottles, such as mustard and honey PP (Polypropylene) Hard, flexible plastic. Ketchup bottles, medicine bottles, aerosol caps, drinking straws PS (Polystyrene) Rigid and brittle plastic. CD jackets, grocery store meat trays, pill bottles, foam packaging peanuts and plastic tableware, take -out containers O (Other) Various monomers and mixtures Other plastics include nylon, acrylic and others. large refillable water jugs, certain “green ” food containers. Lab 3: Intro Chemistry &161 Spring 2021 to Plastics General Chemistry with Lab 1 Duldulao Green River College – Updated 4/16/2021 Page 4 of 7 PRO CEDURE – Work in groups of four for this lab. You will work in the same group of four for the next lab (Sorting Plastics) as well. Your first task is to complete an “everyday encounters with plastics ” survey. This should help you develop a sense of how ubiquitous plastics are in everyday life. You ’ll also attempt to identify ea ch plastic by polymer or r esin ID code, and collect a sample of each one. The samples you collect will be used for the next lab in this course, so be sure to store them in a safe location! Wash your ha nds thoroughly after touching collected p lastics. Do not collect plastics that contain(ed) household chemicals, such as cleaning products, as these may cause skin, eye , or respiratory irritation. Read any precautions on container labels! 1. Conduct a plastics survey at home or other location . Spe nd 30 – 60 minutes inspecting your location , and record the plastics found during that time in a data table (see Table 2 below for an example ) in the Results section of your lab notebook . Rem ember to write in pen anytime you write in a lab notebook! Try to collect plas tic samples of as many different resi n ID codes as possible. This tab le will contain only the plastic samples that you personally collect, and not including plastic samples collected by your lab partners. It’s ok if you yourself have zero plastic samples for a particular code, as long as somebody else in your group has it. NOTE: Make the table take up the entire page of the lab notebook, so that there is plenty of space to write in the Description and Physical Characteristics columns . “Description ” should indicate what the plastic sample was used for, e.g. “ketchu p bottle ”. “Physical characteristics ” can include (but are not limited to) comments on the plastic sample ’s flexibility, thickness, bounci ness, color, stretch /elasticity, transparency or translucency, fragility, or if it makes sound s. Lab 3: Intro Chemistry &161 Spring 2021 to Plastics General Chemistry with Lab 1 Duldulao Green River College – Updated 4/16/2021 Page 5 of 7 Table 2: Example of a Plastic Survey Data Table for One Investigator Code Frequency (total # of items encountered with this code) Description of plastic items and uses Ph ysical Characteristics 1 2 3 4 5 6 7 no code 2. In your lab notebook, c onstruct and fill out another table , called “Table 3 …”, sim ilar to Table 2 above, but it represents the to tal collect ion of p lastic samples of the entire lab group. There must be at least one pl astic sample per code, and at least one plastic sample with no code on it. 3. As a group, choose plastic samples of each code (and a no -code sample) that can be cut into smaller p ieces of approxi mately 1.5 cm x 1.5 cm , and cut them . Only attempt to cut sa mples that can be safely cut! Set th ese cut plastic samples aside for Lab 4. Make a list (“Table 4 ”) of pieces that were cut, identif ying their codes. Make sure that these cut samples are stored in a container or bag with a label, so that you know which code the cut samples belong to! RESULTS (5 pts) Ea ch student in the group needs to record their own results a nd the group results in their own lab notebooks. After completing the procedural steps, the Results section should have a filled - in co pies of the followi ng tables . As usual, all tables in t his class should be properly formatted. • Table 2 • Table 3 • Table 4 ANALYSIS ( 20 pts) Start a section in your lab n otebook after the Results section, and label the section Analysis . Answer the following questions in this Analysis section in your lab notebook in pen. Number each answer a s shown below, and in the following order. Write in complete sentences, and explain in enough detail that your writing is persuasive and logical. Remember to write in a third -person, impersonal style; avoid personal pronouns such as I, you, we, my, our, etc.. Show all work for calculations if any, fol lowing sig rules and using dimensional analysis whe never possible. Lab 3: Intro Chemistry &161 Spring 2021 to Plastics General Chemistry with Lab 1 Duldulao Green River College – Updated 4/16/2021 Page 6 of 7 1. (2 pts) Cr eate a table ( “Table 5 ”) that ranks the resin ID codes from most common (with respect to number of samples collected by the group with that code) to least common. Place the most -common code towards the top of the table, and least common towards the bottom . 2. (2 pts) Calculate the percentage of plastic samples collected by the group that are made of polyethyle ne terephthalate (PET /PETE) . 3. (2 pts) Examining your group ’s PET/PETE samples, what appeared to be the most -common use of the PET/PETE items? 4. (2 pts) How did HDPE rank among samples collected by your group? 5. (2 pts ) What appeared to be the most -common use of the HDPE items? 6. (5 pts) Suggest two possible reasons why the least -common code in your group ’s collection was the least common in the collection , and t wo possible reasons why the most -common code was the most common in the collection. Remember “cause and effect ” when answering “why ”-type s of questions … saying something like “code 7 was the most common because it had the highest freque ncy of all the codes in the collection ” does NOT answer the question! 7. (5 pts) Preparation for Next Lab ! Does your lab group have access to the following items? • Chemistry lab kit, picked up or shipped from GRC • Tea kettle, stove top, microwave, or other method for boiling water • Ove n or toaster oven • Aluminum foil • Clear containers (at least three, to use for density tests) • Vegetable oil or rubbing alcohol (70% isopropyl alcohol preferred) • Table sugar (granulated whi te) Prepare a table ( “Table 6 ”) that summa rizes who has access to each of the items above, along with who has which cut plastic samples. This will greatly affect how you design your experiments for the next lab. Lab 3: Intro Chemistry &161 Spring 2021 to Plastics General Chemistry with Lab 1 Duldulao Green River College – Updated 4/16/2021 Page 7 of 7 Prelab 3 Question Sheet (5 pts) Name Date __________________________ 1. (2 pts) The chemical formula of ethylene ( also known as ethene) is C 2H4. Calculate the molecular mass of ethylene (a) in amu, and (b) in pounds (lb) . 2. (2 pts) Examine Table 1. Which plastic type (by resin ID code) has the repeating unit of highest mass? How massive is it (in amu )? 3. (1 pt) What would be the systematic name of the mo nomer used to make polypropylene, according to general chemistry no menclature rules, as described in Chapter 2 of Silberberg, 9th ed.? Hint: See Table 1, and then review covalent nomenclature rules. Instructions : Answer the following questions , providing all explanations in complete, detailed sentences. Calculations must include all work, using dimensional analysis and following all sig fig rules whenever possible. Submit the finished question sheet on Canvas as a pdf, along with the prelab writeup, by the indicated due date .