What was the change in mass of the contents in the crucible.

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Here is the questions. I will also post the lab results at the end. 1. Record the following: a mass of empty crucible (g) b mass of Mg (g) c mass of the “unknown” product after heating (g) d change in mass (g) 2. Where did the extra mass come from? (Hint: The final product is magnesium oxide) 3. Write a balanced equation for the synthesis reaction that occurred. Experiment 2 1. What was the change in mass of the contents in the crucible. Compare the mass after heating to the mass before heating? 2. The color change of the copper carbonate hydrate as it was heated can help identify the product. Use the following list of copper compounds to indetify the product. CuCO3 – light green powder Cu(OH)2 – blue green powder Cu2O – reddish brown crystals CuO – black powder 3. Given that mass was lost from the copper carbonate hydrate during heating, in this decomposition reaction, how many moles of solid product were produced? The molecular weight of the solid product is 79.545 g/mol (moles = mass / molecular weight). 4. Copper carbonate hydrate produces1 mole of water (MW = 18.015 g/mol) was for every mole of solid product (MW = 79.545 g/mol) produced. Given that 3.327 g of product was produced during the reaction, how many grams of water were released as water vapor? (moles = mass/molecular weight). 5. Write a balanced equation for the decomposition of copper carbonate hydroxide hydrate. Experiment 3 1. What observations did you notice when the hydrochloric acid and zinc were combined? What do these observations tell you about this single displacement reaction? 2. Write a balanced chemical equation for this single displacement reaction. Experiment 4 1. What ions are present in an aqueous solution of NaOH? 2. What ions are present in an aqueous solution of NiCl2? 3. Write a complete, balanced equation for this double displacement reaction. (Hint: the solid is a composed of Ni+2 ions and hydroxide ions.) Dont write the net ionic equation but rather the complete form with neutrally charged compounds with all of the atoms. Lab Results EXPERIMENT ONE Take a crucible from the Containers shelf and place it on the balance. Record the mass of the crucible. mass of crucible is 88 g crucible plus magnesium (Mg). 93 g After using the bunsen burner 1-2 min the weight of the magnesium is 96.289g EXPERIMENT TWO 5 g of copper(II) carbonate hydroxide hydrate (Cu2CO3(OH)2*H2O) weight of copper is 93 g after placing the crucible over the bunsen burner and the copper changing from green to black, the new weight is 91.327 g EXPERIMENT THREE Add 0.25 g of Zinc (Zn) from the Materials shelf to the Erlenmeyer flask. The reaction was a bubbling reaction and the temp continues to drop along with the atm. After attaching the gas syringe the volume is 92.2 ml EXPERIMENT FOUR The nickel chloride solution was green when poured into the beaker. After mixing both substances together the 15 ml of sodium hydroxide remained the same and the nickel chloride turned into a solid, green substance. Additional questions : How many milliliters of 0.883 M H3PO4 will contain the following? (a) 0.39 mol H3PO4 mL H3PO4 the tolerance is +/-9% b) 46.0 g H3PO4 mL H3PO4 the tolerance is +/-9% (c) 7.14 x 1022 molecules of H3PO4 mL H3PO4 the tolerance is +/-9% Determine the molarity of each of the ions present in the following aqueous salt solutions: (assume 100% ionization) (a) 3.65 M CuBr2 Ions: Br+ Br2- Cu2- Br- Br2+ Cu2- Cu2+ Cu2+ [cation+] = M [anion-] = M (b) 0.75 M NaHCO3 Ions: CO32- NaHC+ HCO3- Na+ O3- NaH+ [cation+] = M [anion-] = M (c) 3.01 M K3AsO4 Ions: O4- KAs+ AsO43- AsO4- K+ K3+ [cation+] = M [anion-] = M (d) 0.37 M (NH4)2SO4 Ions: SO3- NH4+ SO42- NH3+ O42- [cation+] = M [anion-] = M Calculate the [H+] for (a) black coffee with a pH of 4.7 (Enter your answer as follows: 1.0E-2 for 0.010) [H+] = M the tolerance is +/-9% (b) black tea with a pH of 6.4 (Enter your answer as follows: 1.0E-2 for 0.010) [H+] = M the tolerance is +/-9% (c) green tea with a pH of 7.4 (Enter your answer as follows: 1.0E-2 for 0.010) [H+] = M the tolerance is +/-9% (d) laundry detergent with a pH of 9.48 (Enter your answer as follows: 1.0E-2 for 0.010) [H+] = M the tolerance is +/-9% Determine how many milliliters of 0.623 M HClO4 will be required to neutralize 56.23 g Ca(OH)2 according to the reaction: _____________ × 10 ____ mL Calculate the pH of solutions having the following [H+]: (a) 0.36 M pH = _________ the tolerance is +/-9% (b) 1.36 M pH = the tolerance is +/-9% (c) 2.6 × 10-5 M pH = the tolerance is +/-9%