100. g Al reacts with excess O2 to produce 150. g Al2O3 according to Calculate the theoretical and percentage yield. 4Al + 302 → 2 Al2O3. 79.4 % 14. Calculate the energy produced by the complete reaction of 150. g H2. 2H2 + O2 → 2H2O + 130KJ 4.83 x 103 kJ 15.
Zing Substances. For ionizing substances, such as NaCl , 1mosm is 1mmole times the number of ions formed when each molecule dissociates. One mmole of NaCl is 58 mg, but when it dissociates, it yields 1 mmole of Na+ (23mg) and 1mmole of Cl ( 35mg). Therefore , 58 mg of NaCl is 2 mOsm of NaCl is put into a beaker and distilled water added to make 1 liter, the osmolarity is 2mOsm/l. A) How many mosm solute will 1 gram of NaCl yield?
Determine the percent yield of this reaction, showing all steps of your calculation. (3 points) heoretical yield of H2 gas: (1.156 x 10^-3 moles)(1 mole H2/ 1 mole Mg) = 1.156 x 10^-3 moles Theoretical mass: (1.156 x 10^-3 moles)(2.02 g/mole) = 2.335 x 10^-3 g Using ideal gas law: P = (1.1 atm)(760 torr / 1 atm) - 19.8 torr = 816.2 torr V = 0.026 L T = 295 K Solve for n: n = PV/(RT) n = (816.2 torr)(0.026
Initial Concentration Chemical Mass of Graduated Cylinder (g) Mass of Sugar (g) Molar Mass (g) Moles in Graduated Cylinder Total Volume (L) Molarity (mol/L) Sugar (C12H22O11) 16.6 10 342.29 .29 .1 .29 Data Table 9. Dilution Series Dilution Volume (mL) Mass (g) Density (g/mL) Initial Concentration (M) Volume Transferred (mL) Final Concentration (M) 0 25.0 mL 25 25 0 mL 0ml 1 25.0 mL 10 10 .29 2.5 mL 5.4M 2 25.0 mL 15 40 .435 4.5 mL 6.8M 3 25.0 mL 20 45 .58 3.0 mL 9.4M 4 25.0 mL 25 50 7.25 6.0 mL 11.2M Data Table 10. Molarity vs. Density Molarity vs. Density molarity is the concentration of a solution given in gram moles of solute per liter of solution. Density is the degree of compactness of a substance. Questions: How would you prepare 10 mL of a 0.25M HCl solution if 1M HCl was available?
If 0.100 mol of hydrogen iodide is placed in a 1.0 L container and allowed to reach equilibrium, find the concentrations of all reactants and products at equilibrium. 2 HI (g) === H2 (g) + I2 (g) Ke = 1.84(10-2 [H2]=[I2]= 1.07(10-2 mol/L, [HI]=7.86(10-2 mol/L 6. A 1.00 L reaction vessel initially contains 9.28(10-3 moles of H2S. At equilibrium, the concentration of H2S of 7.06(10-3 mol/L. Calculate the value of Ke for this system.
Unit 2 ( Isotopes Problem Set 2-2 1. Which of the following are isotopes of element X, with atomic number of 9: [pic],[pic],[pic], and [pic]. 2. For each of the following isotopes, write the nuclear symbols: a. Cu-63, Cu – 65 b. C-12, C-14 c. Mg-24, Mg-25, Mg-26 d. Ne-20, Ne-21, Ne-22 3. Verify that the atomic mass of magnesium is 24.31 amu, given the following information: [pic], mass = 23.985042 amu; percent abundance = 78.99% [pic], mass = 24.985837 amu; percent abundance = 10.00% [pic], mass = 25.982593 amu; percent abundance = 11.01% 4.
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
Part B: The graduated pipet’s average density at 22.3 °C was determined to be 0.9785g/mL with a percentage error of 1.89% shows the graduated pipet to be more accurate and precise. Part C: Density of an unknown NaCl solution was measured and a calibration curve used to determine the percentage of NaCl by mass in the solution. y=0.007x + 0.998 which concluded that the concentration of the sodium chloride solution was 3.14%. INTRODUCTION Anything that you can see, touch, taste or smell, occupies space and has mass, it is called matter. Matter can be a gas, a liquid,
2) Percent recovery for isolation of benzoic acid % Recovery = mass of recovered material _________________________________ x100% mass of starting material = (0.43/1.01) x100% = 42.57% That concludes that the percent recovery is 42,57%. 3) Percent recovery for isolation of hydroquinone dimethyl ether % Recovery = mass of recovered material _________________________________ x100% mass of starting material = (0.16/1.01) x100% = 15.84% That concludes that the percent recovery is 15.84%. Table 2: : Experimental IR peaks compared to literature IR peaks for Benzoic acid Functional groups | Experimental peak (cm-1) | Literature peak (cm-1) | O-H | 3407-2563 | 3400-2564 | C=O | 1689 | 1689 | C-H |
Percent Yield Calculations 1) Balance this equation and state which of the six types of reaction is taking place: ____ Mg + ____ HNO3 ( ____ Mg(NO3)2 + ____ H2 Type of reaction: __________________________ 2) If I start this reaction with 40 grams of magnesium and an excess of nitric acid, how many grams of hydrogen gas will I produce? 3) If 1.7 grams of hydrogen is actually produced, what was my percent yield of hydrogen? 4) Balance this equation and state what type of reaction is taking place: ____ NaHCO3 ( ____ NaOH + ____ CO2 Type of reaction: __________________________ 5) If 25 grams of carbon dioxide gas is produced in this reaction, how many grams of sodium hydroxide should be produced? 6) If 50 grams of sodium hydroxide are actually produced, what was my percent yield?