20. mol H2 reacts with 8.0 mol O2 to produce H2O. Determine the number of grams reactant in excess and number of grams H2O produced. Identify the limiting reactant. 8.1 g H2 , 2.9 x 102 g H2O 17. How many litres of O2 gas are required to produce 100. g Al2O3?
1. 25 cm3 of a solution of 0.1 moldm-3 NaOH reacts with 50 cm3 of a solution of hydrochloric acid. What is the molarity of the acid? 2. 25.0 cm3 of a 0.10 moldm-3 solution of sodium hydroxide was titrated against a solution of hydrochloric acid of unknown concentration.
To do that we had to count the molar mass (M) of zinc sulfate. Then we multiplied the amount of zinc sulfate in moles with the molar mass. Then the answer was the mass (m) of the zinc sulfate to add in grams. M(ZnSO4) = (65.38 + 32.06 + 4 x 16.00) g/mol = 161.44 g/mol n (ZnSO4) = 0.02 mol M (ZnSO4) = 161.44
Results APPEARANCES OF MATERIALS USED Substance Physical Appearance Zinc Carbonate White; powderish Calcium Hydroxide White; powderish; like zinc carbonate 3 M HCL Clear liquid, resembles water 20 mesh granular zinc Grey, metallic, shiny 3% hydrogen peroxide Clear liquid; resembles water Manganese dioxide Very dark grey, black and powdery Copper sulfate Blue, crystalline in structure. Sky blue Zinc iodide Very dark purple, shiny and crystalline in structure 0.1 M acetic acid Clear liquid, resembles water Zinc oxide Very white powdery substance RAW RESULTS Data Specifided (Page 112 CRC handbook) Raw data Volume of Gas Collection Bottle (Average of 3 Trials) 14.04mL Mass of boiling tube (empty) 41.57g Mass of boiling tube with zinc carbonate 43.42g Mass of zinc carbonate 1.75g Volume of water in gas collection bottle after reaction 78.5mL Volume of gas product collected 185.2mL Mass of solid product with boiling tube after reaction 1.11g QUALITATIVE TEST RESULTS Group # Test Observation: Standard Positive/Negative Observation: Experimental Positive/Negative 1 H2 HCL + Zinc bubbling + flaming stick POP! + + flaming splint no POP - 2 CO2 Turned cloudy + Negated from experiment Negated from experiment 3 O2 MgO2 + Hydrogen Peroxide bubbling. Glow stick re-ignited + + wooden splint; glowing stick went out - 4 H2) Added 1 pea size CuSulfate + 1 drop of deionized water; blue, positive + Copper sulfate did not change color when put into wet filter paper - 5 Zn (OH)2 Zinc iodide + 3mL H2O Clear suspension + Visual inspection; cloudy. Acid test= solid + 3M Acetic acid cloudy + 6 ZnO ZnO + Heat yellow Zn Cooled White + ZnCO3 + heat yellow solid.
Conclusion 10 Grams of Potassium chlorate when decomposed produces 3.915576 grams oxygen gas and 6.083363 grams potassium chloride Atomic Weight of Magnesium Introduction In this lab we will determine the atomic weight of magnesium by measuring the amount of hydrogen gas evolved when hydrochloric acid reacts with magnesium. The reaction is as follows: Mg + 2HCl -> H2 + Mg2+ (aq) + 2Cl- (aq) There is a one to one relationship between the number of moles of hydrogen gas evolved and the
Percent H2O in Hydrate is equal 0.34/2.33=14.6% 3. The general formula of barium chloride hydrate is BaClg-nHZO, where n is the number of water molecules. Calculate the theoretical percent water for each value of n—divide the sum of the atomic masses due to the water molecules by the sum of all the atomic masses in the hydrate, and multiply the result by 100. Complete the table. | BaCl2 | BaCl2•H2O | BaCl2•2H2O | BaCl•3H2O | Sum of atomic masses (BaCl2) | 208.23 | 208.23 | 208.23 | 208.23 | Sum of atomic masses (nH2O) | 0 | 18.02 | 36.04 | 54.06 | Sum of atomic masses (hydrate) | 208.23 | 226.25 | 244.27 | 262.29 | Percent water in hydrate (theoretical) | 0% | 7.96% | 14.75% | 20.61% | In this lab we used a Balance, centigram
1 / [CO2] C. [CaO][CO2] / [CaCO3] D. [CaCO3] / [CaO][CO2] _____ 13. The value of Kp for the reaction 2 NO2 (g) [pic] N2O4 (g) is 1.52 at 319 K. What is the value of Kp at this temperature for the reaction N2O4 (g) [pic] 2 NO2 (g) ? A. -1.52 B. 1.23 C. 5.74 X 10-4 D. 0.658 _____ 14.
It has a melting point of 1585K (which is the same as 1312°C 2394°F), heat of fusion of 10,05 kJ/mol, and boiling point of 3546 K( 3273 °C, 5923 °F). Gadolinium has an electron configuration of [Xe]4f 75d16s2; and vapour pressure of7.39 Pa at temperatures of 2000 K.