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Acids and Bases

Solving a Rate Constant Problem

Practice Exercise 13.9 The first-order rate constant for the reaction of methyl chloride (CH3Cl) with water to produce methanol (CH3OH) and hydrochloric acid (HCl) is 3.32 10-10s-1 at 25°C. Calculate the rate constant at 33°C if the activation energy is 116 kJ/mol. My answer, which was incorrect was 3.17e-10. I used th

Treatment for Antifreeze: Administering Ethanol

Treatment for antifreeze poisoning or methanol poisoning generally includes administering ethanol. Why is this effective in combating poisoning by either of these molecules? What is it about methanol and antifreeze that makes it toxic to animals?

Constant-Pressure Conditions of Hydrogen Gas

I'm reviewing for my Chem final and need stuff explained. Please give very in-depth explanations and answers so I can understand how to do it. At 46 degrees C a sample of ammonia gas exerts a pressure of 5.3 atm. What is the pressure when the volume of the gas is reduced to on tenth (0.10) of the original value at the same

Questions I am iffy on

I am completing this class now, reviewing the entire scope of classwork leading to the finals, and there are some review questions I am just real shaky on-and some I simply cannot find an applicable formula for. Thank you! 1. The measured voltage of a cell in which the following reaction occurs is 0.96 V: H2(g, 1.0 atm

Electrolytic refinement of copper

Please describe the electrolytic refinement of copper. What economic advantages offset the cost of electricity for this process? What chemical reactions occur at the anode and cathode?

Solution Properties Examined

Chapter 13 Practice 7. By referring to the figure , determine the mass of each of the following salts required to form a saturated solution in 350 of water at 30 : , , 10. Calculate the mass percentage of in a solution containing 10.8 in 481 water. 13. An ore contains 2.88 of silver pe

Weak Acids and Buffer Solutions

Could you please show me in detail how to do this? 1. Choose an appropriate weak acid from the list below to make 0.25 liter of a 0.1M buffer solution that has a pH of 4.7: AVAILABLE WEAK ACIDS: Acetic acid (Ka = 1.8 x 10⁻⁵) Citric acid (Ka = 8.4 x 10⁻⁴) Benzoic acid (Ka =

Using activities to calculate pH

What is the final pH of a solution that originally consists of 30.0 mL of a citric acid buffer at a pH of 3.26 and an acid concentration of 6.67x10-2 M after 10.0 mL of 0.0750 M HBr is added? The pKa for citric acid is 3.13. Using activities, find the pH of a solution of 0.0167 M Na2SO4 saturated with Mn(OH)2 (Ksp = 2.0×10-

pH of ecosystems

What are some ecosystems that depend heavily on maintaining a specific pH? Why is it necessary to maintain this pH? What is the range of pH's over which this particular system may function? What are some common consequences of deviating from this specific pH?

Convert the following numbers to standard exponential form

I attached a copy of this file if it is better, some of the symbols didnt come through the cut and paste. Thanks. 1. Convert the following numbers to standard exponential form: a) 0.003621 ________________ b) 0.0847 __________________ c) 15 4 ____________________ d) 536.2 x 103 _______________

Oxidation and Reduction Equations

Hey. I don't know how to anser this question. It's 20.22 in Chemistry: The Central Science 11E. Complete and balance the following equations, and identify the oxidizing and reducing agents. Recall that the O atoms in hydrogen peroxide, H2O2, have an atypical oxidation state. b) S (s) + HNO3 (aq) --> H2SO3 (aq) + N2O (

Types of reactions

I have a paper to write on types of reactions. Precipitation, acid-base, and oxidation-reduction reactions. We have to find and discuss and example of each reaction type that has industrial significance. Could you give me some direction?

Acid-Base Equilibria Calculated

1. Calculate [OH-] for 2.170 g of LiOH in 300.0 mL of solution. [OH-] = ? M 2. How many moles of HF (Ka = 6.8 x 10-4) must be present in 0.160 L to form a solution with a pH of 3.30? 3. Calculate the molar concentration of [OH-]ions in a 7.0×10−2 M solution of ethylamine (C2H5NH2) (Kb= 6.4 x 10-4). 4. Calculate

Determine the exact formula of an acid

An organic acid has a molecular weight of 192. A 100 mg sample of this acid was burned in an apparatus. The only compounds that make up this acid are carbon, hydrogen and oxygen. In the U tube apparatus, 137.53 mg of carbon dioxide was caught and 37.8 mg of water was caught. Determine the exact formula of the acid. Make sure tha

Natural Chemistry and Cramps

1. Compare the natural chemistry that takes place in the environment with the chemistry that takes place due to man made factors like pollution. Discuss the effect of pollution at the local, regional, national, and global level. 2. A freshman studying medicine at an Ivy League College is a part of his class crew team and exe

Balancing chemical equations and calculating yield.

When baking soda (sodium bicarbonate or sodium hydrogen carbonate, NaHCO3) is heated, it releases carbon dioxide gas, which is responsible for the rising of cookies, donuts, and bread. The balanced equation for this process is: 2NaHCO3 ® Na2CO3 + H2O + CO2. Calculate the mass of NaHCO3 required to produce 20.5 g of CO2. Plea

Determining the Density in Grams per Cubic Centimeter

Cassiterite (a tin ore) weighing 142.8 grams was placed in a beaker whose volume was 115 ml. The beaker with the ore was then filled with acetic acid and weighed. The ore and acid weighed 230.98 grams. Determine the density of the cassiterite in grams per cubic centimeter. The density of acetic acid is 1.0056 grams/ml at room te

Help calculate the concentrations of OH- and the pH of solutions?

Seven test tubes were prepared as follows: Tube 1: 5 mL of NaOH and 5 mL of water and tubes 2 - 7 were filled with 9 mL of water One mL of tube 1 was then poured into tube 2; 1 mL of tube 2 was poured into tube 3; 1 mL of tube 3 was poured into tube 4; 1 mL of tube 4 was poured into tube 5;1 mL of tube 5 was poured into

pH of test tubes.

Seven test tubes were prepared as follows: Tube 1: 5 mL of 0.1M HCl and 5 mL of water and tubes 2 - 7 were filled with 9 mL of water One mL of tube 1 was then poured into tube 2; 1 mL of tube 2 was poured into tube 3; 1 mL of tube 3 was poured into tube 4; 1 mL of tube 4 was poured into tube 5;1 mL of tube 5 was poured

Calculating Coal Required

How many metric tons of 5% S coal would be needed to yield the H2SO4 required to produce a 4.5 cm rainfall of pH 2.00 over an area of 100 square kilometers? Hint: Calculate vol rain, mol H+, mass of S, mass of coal

Vitamin C Content of Orange Juice Lab

I have attached the sheet I need help with...Here is the info from the lab and my results are in the sheet so far. The prepared iodine solution on the chemicals shelf with a stated concentration of 0.0015M is standardized (confirming the concentration) by performing the following titration: 1. Take a clean volumetric fla

Final pH of NaOH and HA when mixed

What is the final pH at 25oC when 93.0 mL of 0.133 mol/L NaOH(aq) and 50.0 mL of 0.193 mol/L HA(aq) are mixed. Assume that HA is a weak monoprotic acid with pKa=5.31 at 25C. Give your answer accurate to two decimal places.

Weak acid/strong base titration

What is the pH at the equivalence point when when 25.0 mL of 0.175 mol/L HNO2(aq) is titrated with 0.137 mol/L NaOH(aq)? Assume the temperature is 25C. (For HNO2, pKa=3.14 at 25C). Give your answer accurate to two decimal places.

Neutralization, pH and Moles

How many moles of NaOH must be added to 0.400 L of 0.177 mol/L HC3H5O2(aq) to obtain a solution with pH=4.7? Assume the temperature is 25C. (For HC3H5O2, pKa=4.89 at 25C). Give your answer accurate to three significant figures

Acids, Bases and Salts

1. State three examples each of acids, bases, and salts commonly used in therapeutic processes. From the examples you state, select one acid, one base, and one salt and describe how and where they are used in therapeutic processes. Please note that the examples should not duplicate those already shared in your readings 2. A 5

Chemistry and Medical Applications

1. Discuss in detail the healthcare applications of chemical reactions. Which chemical reactions would you consider to be of importance to healthcare professionals? Why? In which situations are these chemical reactions useful to healthcare professionals?

Density and Percent Composition

7. A piece of galena (PbS) with a mass of 504.5 g displaces 48.6 mL of water. What is the density of galena (PbS) ? 8 . Calculate the percent composition of copper in the hydrate CuSO4.5H2O based on atomic weight data. 9. The reaction of sodium hydroxide with nitric acid in water is given by the fol