p1g5+mp4

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=//__ Lab Report __//=

=__ Background Info: __=

= CaCl 2 = = = = NaHCO 3 = = = = Bromothymol Blue (BB) = = = =__ Experimental Design: __= = = = Chemical Reactions Lab = = = = Question: What are some signs that a chemical reaction is taking place? = = = = Hypothesis: Listed under prediction in the chart below. =
 * = Must be tightly sealed, treat hypocalcaemia, odorless, irritates skin, burns skin, causes ulcers if ingested, gives off energy as it dissolves =
 * = Not flammable, uses ice for dust control on roads =
 * = Decomposition reaction: reactant molecule will break down when heated =
 * = Used in baking soda, bread soda, and cooking soda =
 * = 3 Oxygen atoms =
 * = Both ionic and covalent =
 * = Turns acidic substances yellow and bases green =

= Independent Variable:Combination of chemical in the test tube =

= Dependent Variable: Signs of a chemical reaction =

= Constants: Amount of each substance =

> = to 19.3 o C = > = = || * = NaHCO 3 dissolved into H 2 O = || = CaCl 2 = || = Precipitate formed = || * = 8 grams of NaHCO 3 = =__ Pictures: __= = = =__** Summary: **__=
 * =__ Combination __= || =__ Prediction __= || =__ Observation __= || =__ Actual Outcome __= ||
 * = CaCl 2 + BB = || = A color change will occur. = || * = Lighter shade of blue =
 * = Some dissolved =
 * = Temperature increased = || * = Color change = ||
 * = NaHCO 3 + BB+ CaCl 2 = || = They will dissolve into each other and make a color change. = || * = Color change to greenish-yellow =
 * = Fizzed =
 * = Temp was 22.6 o C = || * = Color Change =
 * = Gas Formed = ||
 * = CaCl 2 + H 2 O = || = A gas will be formed. = || * = Fizzed and dissolved =
 * = White chalky color =
 * = Temperature changed from 20.1 o C to 40.3 o C = || * = CaCl 2 dissolved into H 2 O = ||
 * = NaHCO 3 + BB = || = They will dissolve into each other. = || * = Temperature dropped from 20.1 o C =
 * = Same color = || * = NaHCO 3 dissolved into BB = ||
 * = NaHCO 3 +CaCl 2 + H 2 O = || = An odor will be produced. = || * = Fizzed and bubbled =
 * = Foggy white color =
 * = Temperature slightly increased = || * = Gas Formed =
 * = Color Change = ||
 * = NaHCO 3 + H 2 O = || = They will create a gas. = || * = NaHCO 3 dissolved and settled onto the bottom =
 * = Temperature of H 2 O went from 20.1 o C to 19.0 o C =
 * ~ = NaHCO 3 + =
 * = 1.3 grams of CaCl 2 =
 * = Slight temperature increase =
 * = Clumpy texture = || * = Precipitate Formed = ||

= Our groups predictions varied for each combination. = = = = NaHCO 3 + BB: We made a prediction that NaHCO 3 + BB would result in the substances to dissolve. The starting temperature of BB was 20.4 o C, and the weight of the NaHCO 3 was 0.8 grams. Our results were that the substance dissolved, but some still stayed at the bottom. There was a temperature decrease of 19.3 o C. We found no evidence of an odor or color change. = = =

= CaCI 2 + H 2 O: We made a prediction that CaCI 2 + H 2 O would form gas bubbles. The starting temperature of the water was 20.1 o C. The results showed an increase in temperature of 40.3 o C. The product dissolved in the water, but some residue had settled at the bottom. The color of the product was a chalky white color, and opaque. Our group found no evidence of an odor. = = =

= CaCI 2 + BB: Our groups prediction was that there would be a color change after the substances were mixed. The temperature of the BB before the experiment was 20.4 o C. The weight of CaCI 2 was 1.3 grams. Our results showed and increase of temperature to 37.2 o C, and the color of the combination was a lighter shade of blue. There was some residue in the bottom of the test tube from the mixing of CaCI 2 and BB, but overall the the product was transparent and dissolved. = = =

= NaHCO 3 + CaCI 2 + BB: The prediction was that the substances would dissolve into each other and form a color change. Our starting temperature of BB was 20.4 o C. the substance fizzed and bubbled and had a white foggy color. A color change and gas bubbles were proof of the chemical reaction. Our temperature slightly increased to 22.6 o C. = = =

= NaHCO 3 + H 2 O: Our prediction is that gas bubbles would form. The results is that the temperature dropped from a starting temp. of 20.1 o C to 19 o C. In addition, there was no color change, and the NaHCO 3 settled at the bottom of the test tube. Like the other experiments the combination did somewhat dissolve. = = =

= NaHCO 3 + CaCI 2 + H 2 O: The prediction from our group is that an odor would be produced. The temperature of the water when we started was 20.1 o C, and the weight of the NaHCO 3 was 0.8 grams. The weight of CaCI 2 was 1.3 grams. From the ending results, the temperature increased to 21.0 o C. The product fizzed and there was no sign of an odor. The color was a chalky white, and was opaque. = = =

= NaHCO 3 + CaCI 2 : We made a prediction that a precipitate would form. From the results, the temperature slightly increased and the texture of the product was rough and clumpy. = = = =__** Conclusion: **__= = The 7 different chemical reactions produced many different results and were very different from our hypotheses. The gas bubbles that were formed were a sign of the evolution of a gas. A color change also showed a chemical reaction occurred in the substances. Some substances didn't go through a chemical reaction because the substances only dissolved into each other. None of the substances formed a precitate or had a change in odor, but these things signify a chemical reaction. The decrease in temperature was a sign of an exothermic reaction, while an increase in temperature was a sign of an endothermic reaction. Overall, there are many signs of a chemical reaction. =



=//__ Lab Report __//= = = =__ Background Information: __=

=// REACTANTS //= = Lead Nitrate- Pb(NO 3 ) 2 : = = Hazards = = = = Sodium Iodide- NaI: = = Hazards = = = =// PRODUCTS //= = Sodium Nitrate-NaNO 3 : = = = = Lead Iodide-PbI 2 : = = Hazards =
 * = In the form of a colorless crystal or a white powder =
 * = It is soluble in water =
 * = Used in pigments in lead paint =
 * = Toxic =
 * = Cannot be inhaled =
 * = Cannot be ingested =
 * = Can't come in contact with skin =
 * = In the form of a white crystal =
 * = Used in radiation detection and treatment of iodine deficiency =
 * = Cannot be inhaled =
 * = Cannot come in contact with eyes or skin =
 * = It is in the form of a white powder or colorless crystal =
 * = Used in fertilizer and smoke bombs =
 * = Has a sweet odor =
 * = Has a bright yellow color at room temperature =
 * = Used to detect materials at high energy levels =
 * = Was once used in paint, but it is not anymore because it is harmful =
 * = Toxic =

=__ Prediction: __= = Our prediction was that the mass of the reactant would be less than the products, which was incorrect. =

=__ Experimental Design: __=

Constants: The substances (Lead Nitrate and Sodium Iodide), the beaker, and the two test tubes
=__ Data: __= = = = = =   = =__ Observations: __=
 * = Lab Group = || = Mass of Glassware (grams) = || = Reactants & Glassware (grams) = || = Reactants (grams) = || = Products & Glassware (grams) = || = Mass of Products (grams) = || = Change in Mass (grams) = ||
 * = 1 = || = 94.2 = || = 99.2 = || = 5.0 = || = 99.1 = || = 4.9 = || = -1 = ||
 * = 2 = || = 95.5 = || = 99.5 = || = 4.0 = || = 99.5 = || = 4.0 = || = 0 = ||
 * = 3 = || = 80.1 = || = 84.4 = || = 4.3 = || = 84.5 = || = 4.26 = || = +.1 = ||
 * = 4 = || = 82.2 = || = 86.4 = || = 4.2 = || = 86.5 = || = 4.2 = || = 0 = ||
 * = 5 = || = 74.4 = || = 79.0 = || = 4.6 = || = 79.0 = || = 4.6 = || = 0 = ||
 * = 6 = || = 92.9 = || = 96.9 = || = 4.0 = || = 96.7 = || = 3.8 = || = -.2 = ||
 * = 7 = || = 88.3 = || = 92.0 = || = 3.7 = || = 92.0 = || = 3.7 = || = 0 = ||

= When the lead nitrate and sodium iodide were poured into the same beaker, a bright yellow substance was created. The new substance contained the products of the reaction and was opaque, transparent, and had a uniform composition. The products that resulted from the chemical reaction were lead iodide and sodium nitrate. There was also no change in mass throughout the lab. =

=__ Chemical Equation: __=


 * Pb(NO3)2 + 2NaI **[[image:mrslagunasclass/arrow-blue-outline-right.png width="40" height="27"]]** 2NaN ****O3 + PbI2 **
 * Double- replacement Reaction! **

=__ Pictures: __=





=__ Summary: __=

= The Law of Conservation of Mass states that mass cannot be created or destroyed in chemical and physical changes. Our hypothesis said that the mass of the reactants would be less than the mass of the products, when a precipitate was formed, was wrong. Our data concludes that the mass of the reactants was 4.6 grams, and the mass of products was 4.6 grams. This proves the Law of Conservation of Mass because the mass was equal in the reactants and the products, since mass cannot be created or destroyed. =

=**__ Conclusion: __**=

= The mass of the reactants was equal to the mass of the products, when a precipitate was formed. The mass was the same in the reactants and the products because of the law of conservation of mass. The law of conservation of mass states that mass is not created or destroyed in a chemical reaction, so even though a precipitate was formed, the mass of the products and the reactants was the same. Also, the reaction is a double replacement reaction so the lead nitrate and sodium iodide broke down and formed different compounds, such as sodium nitrate and lead iodide. Since the same amount of each element was in the compounds in both the reactants and the products, the mass stayed the same. Due to the law of conservation of mass, the mass of the reactants and the products stayed the same. =