Purpose: The purpose of the lab is to correctly describe and distinguish samples and models of elements, compounds, and mixtures.
The lab asks you to examine conceptual models of matter in which atoms of one element are represented by nuts while atoms of another element are represented by bolts. After examining each model, complete the following tasks:
a. sketch a representative molecular picture of the model;
b. describe the composition of the model in words (does the model contain atoms, molecules, or both?; does the model represent elements, compounds, or both?; does the model represent a pure substance or a mixture?)
c. write the "chemical formula" of the model, using B as the symbol for a bolt and N for a nut.
Lab report requirements: Answers to the pre-lab questions, as well as the lab report should be word processed. The table below, which should be included in your report, should also be in your lab notebook in order that you have a permanent record of your observations. We've provided data recording templates below, you need to set up something similar in your lab notebook. There will be eight (8) models to record.
Pre-lab questions:
To help you start thinking about what a pure substance, compound, mixture, looks like, it's important to think about how you would indicate it through words. As you have learned, each element is given an individual name. As you will learn, compound names reflect the elements that make them up. Names of mixtures in turn are reflected by the elements and/or compounds that are in the mix.
1. Considering that we name many mixtures with one or two words ("milk", "coca cola"), is this representative of what a mixture is made of chemically? (Go check the ingredients label for either of these.)
No, the name given to the mixture does not represent what the mixture is chemically made of. It only represents the final mixture.
2. How many names would you need if you were given a pure