1. Experimental Determination of an Empirical Formula 2/12/16

2. Introduction According to the atomic theory, in ordinary chemical reactions, an atom cannot be divided into smaller parts. Therefore, when two elements combine, they must do so in small whole number ratios. In order to experimentally determine an empirical formula, you will oxidize tin by treating it with nitric acid. You will then calculate the mole ratio of the two elements (oxygen and tin) in the product and predict a formula for the product.

3. Purpose In this experiment, you will react a carefully determined amount of tin with excess nitric acid and calculate the mole ratio of tin and oxygen in the product. YOUR PURPOSE: 3-5 sentences in your own words.

4. Equipment Include the equipment used in your write up. If you would like to use nitrile or latex gloves, you must bring your own.

5. Procedure As always, this must be included in your write up. MAKE SURE YOU UNDERSTAND WHAT YOU ARE GOING TO PERFORM BEFORE THE LAB. Read through the procedures for hints on how to answer the pre-lab questions.

6. Nitric acid (HNO 3 ) Potential Acute Health Effects: Very hazardous in case of skin contact (corrosive, irritant, permeator), of eye contact (irritant, corrosive), of ingestion,. Slightly hazardous in case of inhalation (lung sensitizer). Liquid or spray mist may produce tissue damage particularly on mucous membranes of eyes, mouth and respiratory tract. Skin contact may produce burns. Inhalation of the spray mist may produce severe irritation of respiratory tract, characterized by coughing, choking, or shortness of breath. Prolonged exposure may result in skin burns and ulcerations. Over-exposure by inhalation may cause respiratory irritation. Severe over-exposure can result in death. Inflammation of the eye is characterized by redness, watering, and itching. Skin inflammation is characterized by itching, scaling, reddening, or, occasionally, blistering.

7. Date of lab: 2/17/16 You must have all pre-lab questions (Write the entire question out then answer), purpose, and procedures completed before you perform the lab. You will have to do a virtual lab, with twice as many calculations, twice as many pre-lab questions, and twice as many post lab questions. Your choice.