chemistry 1a. Urea [(NH2)2CO] is produced by reacting ammonia with carbon dioxide with the release of water. In one process 637.2g of ammonia is treated with 1142g of carbon dioxide A. Write a balance equation for the above reaction B. Which of the 2 reactants is the limiting reagent C. Calculate the mass of urea formed D. How much excess reagent is left at the end of the reaction E. If the actual yield of urea formed was 980g what is its yield % a. Ans.
Objective To determine of heats from three exothermic reactions and investigate the Hess Law Summary Based on this experiment, we have study three related exothermic reactions involving sodium hydroxide. The first reaction (Part A), solid sodium hydroxide will dissociate into water. The heat produce by this reaction (∆H1) and this called as the heat of solution of solid NaOH. From the experiment we have managed to determined that ∆H1 = -41.84 KJ/mol In the second reaction (Part B), an aqueous solution of NaOH is allowed to react with an aqueous solution of HCl. This is a neutralization reaction between a strong acid and strong base.
4 Calculate the molar mass of these compounds: (relative atomic masses: H = 1; N = 14; O = 16; S = 32; Cu = 64; Br = 80; Pb = 207) (a) copper nitrate, Ca(NO3)2 (b) lead bromate, Pb(BrO3)2 (c) ammonium sulfate, (NH4)2SO4 5 The equation for the complete combustion of methane is shown below. CH4 + 2O2 → CO2 + 2H2O When 80 g of methane is completely combusted, 220 g of carbon dioxide and 180 g of water are formed. (a) Why is the mass of carbon dioxide formed greater than the mass of methane burnt? (b) Calculate the mass of oxygen that reacted. (c) Calculate the mass of water formed when 20 g of methane undergoes complete combustion.
Sodium Hydroxide + Hydrochloric Acid Sodium Chloride + Water NaOH(aq) + HClaq → NaCl(aq) + H2O(l) Variables Independent The independent variable of the experiment was the amount of sodium hydroxide that we added to the acid. To keep the variable controlled we would measure 1 ml of the sodium hydroxide and pouring that to the hydrochloric acid. Dependent The dependent variables of the experiment were the temperature and the pH number of the mixture. To control the pH and temperature use the electronic probe and data logger. Controlled The controlled variables of the experiment were: A.
At the other electrode (cathode), hydrogen gas is liberated at the surface through the reduction of hydrogen ions in the aqueous sulfuric acid solution. The reaction is: 2 H+(aq) + 2 electrons -> H2(g) This experiment is based on the mass loss of the copper anode, but it is also possible to collect the hydrogen gas that is evolved and use it to calculate Avogadro's number. Materials * Direct current source (battery or power supply) * Insulated wires and possibly alligator clips to connect the cells * 2 Electrodes (e.g., strips of copper, nickel, zinc, or iron) * 250-ml beaker of 0.5 M H2SO4 (sulfuric acid) * Water * Alcohol (e.g., methanol or isopropyl alcohol) * Small beaker of 6 M HNO3 (nitric acid) * Ammeter or multimeter * Stopwatch * Analytical balance capable of measuring to nearest 0.0001 gram Procedure Obtain two copper electrodes. Clean the electrode to be used as the anode by immersing it in 6 M HNO3 in a fume
Oxygen: B. Reacts the same as hydrogen with gas bubbles rising to the surface. F. I believe we fill the gas generator test tubes almost to the top with the chemical s to eliminate as much air as possible and to speed up the gas transfer to the pipet. 3. Hydrogen and Oxygen Mixture G. A balanced equation for the reaction between Hydrogen and Oxygen is 2H2 + O2 -- 2H2O Data Table: Experiment Results | Gas | Flame reaction | Glowing splint | Limewaterreaction | BromothymolBlue reaction | Hydrogen | Small Poof with flame, then blew flame out | | | | Oxygen | | Glowing splint flamed back up when inserted | | | Hydrogen & Oxygen | | | | | Carbon Dioxide | Puts the flame out | | Turns the limewater a milky color | Turned the blue water to a yellow color | Alka Seltzer | | | Increased the volume of the water/add CO2 | | Breath | | | I saw no reaction | | Questions: Questions: A. We fill the gas generator tubes almost to the top to eliminate as much air as possible and speed up the gas transfer to the pipet.
3) Consider the following equation: N2(g) + O2(g) 2NO(g) a) Is this reaction exothermic or endothermic? b) Calculate the amount of heat transferred when 16.4 kg of NO(g) reacts. H = 180.7 kJ 4) A 2.64 g sample of hydroquinone (C6H6O2) was combusted in a bomb calorimeter. 234 calories of energy was generated. The temperature rose from 25.0°C to 34.9°C.
Due to this, the reaction takes place in acidic conditions by adding concentrated sulfuric acid to the solution. The sulfuric acid protonates the alcohol group in triphenylmethanol. The ether is formed when the carbocation reacts with methanol to form trityl methyl ether. H3O + + CH3OH Triphenylmethanol Trityl Methyl Ether Procedure: Approximately 0.1g of triphenylmethanol crystals was placed into a reaction tube and grinded to fine powder with a glass rod. 1ml of concentrated H2SO4 was then added to the tube and the solution was continuously stirred to dissolve all the triphenylmethanol.
Gently stir the pellets until the acid is dissolved by shaking the the apparatus. Lift the calorimeter lid and wash out its contents and the thermometer. Repeat this experiment using 50.0 mL of 1.0M acetic acid. Repeat experiment using 25.0 mL of each 2.0M sodium hydroxide and 2.0M acetic acid. Data Table(s): Reaction equation Mass of solid NaOH Initial Temp.
The ultimate goal of this experiment is to synthesize benzocaine from p-nitrotoluene. In order to achieve this, the following multiple steps will be employed: 1. The reduction of p-nitrotoluene to create p-methylaniline. The reducing agent for this phase is a metal –acid combination, tin and hydrochloric acid. 2.