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Acids and Bases

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

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

Acids and Bases

Which of the following is a property of acid solutions? a. sour taste c. change red litmus to blue b. slippery feel d. more than one response is correct A 25.00 mL sample of hydrochloric acid solution, HCl, is titrated with 0.0512 M NaOH solution. The volume of NaOH solution required is 21.68 mL. What is the molarity of

Solutions and pH molar concentrations

The molar concentration of H+ ions in a solution is 5.8 × 10-9. The pH of the solution is a. 9.00 c. between 8.00 and 9.00 b. 5.80 d. between 9.00 and 10.00 A solution for which [OH-] = 3.0 × 10-10 is classified as a. acidic c. neutral b. basic d. more than one response is correct 10. A solution has a pH of 11.60. Th

Given [OH-], determine pH, acidic/basic/neutral

A water solution is found to have a molar OH- concentration of 3.2 × 10-5. The solution would be classified as a. acidic b. basic c. neutral d. can't be classified What salt would be produced by the reaction of H2SO4 with LiHCO3? a. Li2S b. LiSO4 c. Li2SO4 d. Li2CO3 7. The molar concentration of OH in a water solution i

Concentrations and Solutions

1) The Equilibrium constant Kp for the reaction 2SO2(g) + O2(g) --- 2SO3(g) Is 5.60 x 10^4 at 350 degrees C. The initial pressures of SO2 is 0.350 atm and the initial pressure of O2 is 0.762 atm at 350 degrees C. When a mixture equillibtrates, is the total pressure less than or greater than the sum of the in

Characteristics of Acids and Indicators

1.) Methyl red is a common acid-base indicator. It has a Ka equal to 6.3 x10-6. Its un-ionized form is red and its anionic form is yellow. What color would a methyl red solution have at pH = 7.8? green red blue yellow violet 2.)The Ksp value for lead(II) chloride is 2.4 x 10-4. What is the mol

Five pH and pOH problems are presented, solved, and fully explained.

1. If the pH of an aqueous solution is 8.23, what are the hydrogen- and hydroxide-ion concentrations of this solution? 2. If 7.40 grams of Ca(OH)2 is dissolved in sufficient water to make 100mL of solution, what is the hydroxide-ion concentration of this solution? 3. What is the hydroxide-ion concentration, the pH, and the hyd

Making a Buffer

Calculate the volume (100mL) of the 0.1M dihydrogen phosphate (monobasic)and the volume of the 0.1M monohydrogen phosphate (dibasic) that are required to make a buffer at pH 7.4. Ka Monobasic=6.2x10^-8 Ka dibasic=4.8x10^-13

Dilution Chemistry Problems

1.)If I wanted to make 50ml of a 1/20 dilution of a 0.1 M salt solution, how would I go about doing this; meaning what volume of 0.1 M salt solution and what volume of water would I need to add? 2.) If I wanted 10ml of a 1mM nitrophenol solution and all I had on hand is a 50 mM nitrophenol solution, how would I make it? 3.

Calculate pH and % Ionization from Ka

I'm given the Ka and concentration to calculate the pH then find % ionization. I utilized an ice table and made the assumption that x << the # i'm working with, however, when I check the assumption... its not < 5% snd plugged my #'s into the quadratic formula and both #'s check... when one # is usually eliminated and I'm left wi

Reactions and Properties of Oxygen Compounds

1. balance equations:----> (equals heat ) NaNO3 ----> NaNO2 + O2 SiO2 -----> no reaction PbO2 -----> PbO + O2 MgO -------> no reaction KClO3 -----> KCl + O2 2 .Rocks and soil on the Moon, as on the Earth, consist mainly of silicon-oxygen compounds, called silicates. What is the chance that astronauts could easil

Gravimetric Analysis

Describe the basic steps involved in gravimetric analysis. How does this procedure help us determine the identity of a compound or the purity of a compound if its formula is known? Explain. Answer needs to be in a 200-300 word response in essay form.