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?
Reactions Lab David Vaghari INSTRUCTOR: Dr. Chernovitz Monday, July 23, 2012 Oxygen Production Introduction In this lab, potassium chlorate will be decomposed producing oxygen gas and potassium chloride. The hypothesis is that the reaction will yield 3.916 grams of oxygen gas. Materials Test tube 10 grams potassium chlorate Bunsen burner Procedure Step 1. Obtain a test tube, place a 10 gm of potassium chlorate. Step 2.
A student focus on a specimen at low power and carefully centers it before changing to high power. At high power, however, he doesn't see the part of the specimen he was interested in. What might be the problem? The object the student is looking at is not circular, and possibly one part (in which s/he might be interested) extends far to one side, thus out of the field of view at the higher magnification. Change the lighting, If there is too much light, things can appear bleached out.
0.00512 * 500 = 2.56 c. 0.00806 * 319.9= 2.56 d. 0.00806 * 319.9 = 2.56 500 mL =0.5 L e. 0.0161 * 500 / 2 =2.56 4. Exercise 4: a. 0.250M; 250 mL 0.25 L (0.25) (0.25) = 0.0625 moles ZnI2 b. Prepare the solution by dissolving 19.95 grams of Zinc Iodide with 250 mL of water. c. Prepare the solution by dissolving 38.90 grams of ZnI2 with 500 mL of water.
Garraud Sobner General Chemistry, Experiment II 02/11/2012 Questions: 1- In, part I which volume determination was more accurate? Explain. A- 2nd method with the graduated cylinder is more accurate. But not only because we found it more difficult to read the ruler. It was also because we had to take two measurements (one for diameter another for height)...which could possibly create more mistakes.
Heat flows from the warmer to the cooler object until they are both at the same temperature. Conduction is the movement of heat through a substance by the collision of molecules. At the place where the two object touch, the faster-moving molecules of the warmer object collide with the slower moving molecules of the cooler object. As they collide, the faster molecules give up some of their energy to the slower molecules. The slower molecules gain more thermal energy and collide with other molecules in the cooler object.
Solution Stoichiometry and Gas Law Problems Problem 1 In flask A, 1.500g of silver nitrate solid is dissolved in 50.0mL of water, while in flask B, 0.500g of potassium carbonate is dissolved in 25.0mL of water. The two solutions are then mixed together. a) Before mixing, what is the molarity of each solution? b) Write the balanced molecular equation, the complete ionic equation, and the net ionic equation for the reaction. c) If the percentage yield is 85.0%, what mass of precipitate is actually produced?
Calculate the molarity of the original vinegar solution and its concentration in gdm-3, given that it reacts with NaOH in a 1:1 ratio. 7. 2.5 g of a sample of ethanedioic acid, H2C2O4.nH2O, was dissolved in water and the solution made up to 250 cm3. This solution was placed in a burette and 15.8 cm3 were required to neutralise 25 cm3 of 0.1 moldm-3 NaOH. Given that ethanedioic acid reacts with NaOH
Used |B.P/M.P |Density |Structure | |Cyclohexane |84.16amu |“25ml” |80.74° C |0.779g/mL (l) |[pic]2 | |Benzoic Acid |122.12amu |1.00g |250°C |1.27g/ml |[pic]3 | Procedure/Observations 1.) Filtration/Recrystallization: Benzoic acid (1.00g) was weighed in a beaker (250ml). After adding distilled water (100ml) the beaker was heated with a Bunsen burner until the solid dissolved. After the solution sat to cool some solid recrystallized. The liquid was cooled in
Substances undergoing net diffusion are said to move down or with their concentration gradient. After time (dependant on the substance) the substance will become evenly distributed. This is what’s known as equilibrium, although random kinetic motion continues, there’s no further net diffusion. Certain attributes can affect diffusion, such as heat, this will make diffusion occur more rapidly due to transferring more energy to the molecules to move around faster. Also a larger concentration gradient produces a faster diffusion, and smaller molecules diffuse more rapidly than larger molecules.