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Laboratory 1: PHYSICAL & CHEMICAL PROPERTIES OF HOUSEHOLD SUBSTANCES:
Lab # 1 -Proc.1. Solubility Tests: It is crucial that you only use very small amounts of the solids as larger amounts will obscure whether it dissolves. You need to stir vigorously and be patient to see if most of the solid will dissolve.
Lab # 1 - On the Observation / Data page complete the observations and results of the tests. Record the name, and the formula, as well as, any significant observations. Look at the Introduction to find the name and formulas of the compounds used in this lab. Practice writing the chemical formulas. Put the numbers in the formulas as small subscripted numbers.
List all of the compounds that are soluble in water - these will appear as an almost clear liquid. Those that are insoluble will appear as white milky or white with solids floating or on the bottom. Those that are partially soluble will appear to have a slight cloudiness present. Salt, although considered soluble may have a slight cloudiness from an anti caking ingredient present.
Lab # 1 - Ques. 7: Make sure that you use as your examples substances and solutions from this lab or element inventory. Use your text or resources from the internet for the definitions. Make sure to include the definition as well as an example of each for full credit. First write a brief definition, then follow up with an example from this lab.
Laboratory # 2 - COMBUSTION, HEAT, AND CALORIES
Lab # 2 - Ques. 1: Try to think about this question at the molecular level. What are the molecules doing? Be specific in talking about the water molecules or the copper atoms. Which ones are moving faster? slower? - relate to temperature? This is really very similar to the process described for heating the hot water tank.
Lab # 2 - Data - Final Temp in cup and Final temp of the quarter: The final temperature in the cup may be only 1 to 3 degrees higher than the initial temperature. Think carefully about what has happened to the temperatures of the zinc bar and the water in the cup. One substance is losing heat while the other is gaining or absorbing heat. This is represented in the change of temperatures from the initial to final temperatures of both the zinc bar and the water. The zinc bar has a very large temperature difference 60-80 degrees from its initial temperature in the boiling water to the final temperature of the water in the cup.
Lab # 2 - Calculations: Calories of heat transferred. In this first step just multiply the quantities. Use the specific heat number as is so that the units if applied correctly will cancel so the the final number has units of calories.
Lab # 2 - Ques. 2: Percentage Calculations are based upon the general formula:
Percentage equals part divided by whole multiplied by 100 (that is the same as moving the decimal two places to the right.) The "part" is the absolute difference between the experimental answer and the actual answer. The "whole" is the actual specific heat.
Lab # 2 - Part II. Calculations - heat absorbed by water
In reality this calculation involves the multiplication of the weight of water and the temperature change of the water. The specific heat of water is 1.0, so this does not change the calculation at all, but does allow the cancellation of the units so that the final answer is in calories.
Home Laboratory # 3 : ABSORPTION OF SOLAR RADIATION - GREENHOUSE EFFECT
Laboratory # 4: ACIDS AND BASES IN RAIN, LAKES, STREAMS, AND SOILS
Lab #4 - QUES. 3: As you try to answer this question, look for some slight differences between the pure acid and the acid that has reacted with the TUMS. Look for the direction of the pH change. Has the pH increased which means that there is less acid present? The pH may not quite reach 7 under these conditions.