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# Acids and Bases

### The Value of Kb

The value of Kb for methylamine, (CH3)2NH, is 7.4 x 10 ^ -4. What is the pH of a solution containing 0.32 M dimethyl ammonium ion, (CH3)2NH2 + ?

### Glucose Synthesis Problems

Glucose is soluble in benzene. If alpha-D-glucose is dissolved in benzene, essentially no alpha-D-glucose is formed. However, if small amounts of phenol and pyridine are added, then the equillibrium amount of alpha-D-glucose is formed but slowly. If, to a solution of alpha-D-glucose in benzene, a small amount of 2-hydroxy-py

### Conversion formula between pressure units

What is the formula for converting atm to Torr? example: 1.87 atm to Torr Also what is the formula for converting Torr to mmhg? example: 748 Torr to mmHg What about mb to kPa? example: 998mb to pKa Then in. Hg to atm example:26,88 in Hg to atm

### Hydrogen Ion Concentration

How do you find hydrogen ion concentration, and which of the following have the highest concentration? 55.6M H2O 0.25 M HCl 1.0 M CH4 1.2 M NaOh 0.20 M NaH

### Acid-Base Equilibria

1. Write formulas for the conjugate bases for each of these acids: a) HCl b) CH4 c) HSO3- d) H2SO4 e) NH3 2. In the following reactions, identify the Lewis acid and the Lewis base: a) Fe3+ + 6H2O &#8592;&#8594; Fe(H2O)36+ b) BF3 + NH3 &#8592;&#8594; F3BNH3 c) BF3 + F- &#8592;&#8594; BF4-

### Chemistry Element Questions

1. What is the volume of 1.20 x 1022 molecules of nitric oxide gas, NO, at STP? 2. What is the mass of sodium phosphate (163.94 g/mol) that yields 1.00 g of calcium phosphate (310.18 g/mol) precipitate? __CaCl2(s) + __Na3PO4(aq) &#8594; __Ca3(PO4)2(s) + __NaCl(aq) 3. How many moles of calcium metal react to yield 0.50

### Calculating solubility of aluminum in aluminum sulfate (AL2(SO4)3) at various pH levels?

Alum (aluminum sulfate) is used as a flocculant to floc an anionic material in a water solution at pH = 4.0 and temperature = 130 degrees F. The solubility of the alum is noted as 87 grams per 100 cc's of liquid (assuming std temp & pressure). Assume 1 liter of solution....based on this, how would I determine the actual solub

### Calcium carbonate in limestone

The white limestone cliffs of Dover, England, contain a large percentage of calcium carbonate (CaCO3). A sample of limestone with a mass of 84.4 g reacts with an excess of hydrochloric acid to form calcium chloride. CaCO3 + 2HCl ----> CaCO3 + CaCl2 + H2O + CO2 The mass of calcium chloride formed is 81.8 g. What is the percen

### the density (in g/L) of the CO2

A 1004.0-g sample of CaCO3 that is 95.0% pure gives 225 L CO2 at STP when reacted with an excess of hydrochloric acid. CaCO3 + 2HCl -- > CaCl2 + CO2 + H2O What is the density (in g/L) of the CO2?

### Acid-Base Calculations

1.) Calculate the four values of pH, pOH, [H+], and [OH-] for a 0.100 M of HCl. 2.) Calculate the four values of pH, pOH, [H+], and [OH-] for a 0.00250 M NaOH solution. 3.) Calculate the four values of pH, pOH, [H+], and [OH-] fo a 0.00150 solution of nitric acid (HNO3). 4.) The Ka of HCl is known to be about 10^7. What is th

### Mole, Mass, Enthalpy, and Energy Change Problems

See attached file for full problem description. 1. Which is not a solution? brass, fog, hydrochloric acid, or wine 2. How Many Moles of CuO can be produced from 0.0450 mol if Cu2O in the following reaction? 2 Cu2O(s) + O2(g) -> 4 CuO(s). 3. Methane and Oxygen react to form carbon dioxide and water. What mass of wa

### pH Adjustment of a Solution with NaOH or Ca(OH)2

Assume you have a 64000L volume of solution (predominantly water) with a pH of 4.03. 1. How much NaOH would be required to raise the pH to 5.5? 2. Or, if using Ca(OH)2 --- how much calcium hydroxide would be required to raise the pH of this solution to 5.5? In each case, assume full ionization of the base.

### Compound and Examples...

What is a reactive compound and state two examples?

### Sulfric acid H2SO4

A 0.21g sample of sulfuric acid is dissolved completely in water to make 0.25 litre of final solution. Calculate the hydrogen ion concentration in mol 1 - 1 in this solution. In scientific notation and significant figures.

### Calculating mass of sulfuric acid to affect pH change?

I have a 2 part question concerning the use of H2SO4 to adjust the pH of a solution: 1. How many grams per liter of H2SO4 is required to adjust the pH of a solution from 3.8 to 2.8 assuming the sulfuric acid fully ionizes? 2. If in reality however, the actual sulfuric acid ionization/dissociation is a 2 step process and no

### Forming Aluminum Hydroxide from Aluminum Sulfate and Water

Assume we have a 1000L tank of water and very dilute weak acids. To this tank we add and dissolve 260 grams AL2(SO4)3 (solid granules) --- the resultant pH is 4. The intention is to form AL(OH)3 solids/particles in this reaction. Question 1: How much Al(OH)3 will be formed in this reaction at pH=4.0 Question 2: If the pH w

### Calculate amount of NaOH to raise an acetic acid and water pH

Please walk me through the calculation of determining how much NaOH is needed to raise a 1 liter solution of acetic acid and water with a pH of 4.5 to a final pH of 6.0 ---- this would be at 25 degrees C? What happens in this system if temperature is 55 degrees C?

### Acid Base Titration

A 0.394 sample of potassium hydrogen phthaate (KHC8H4O4) is dissolved in 100-Ml of water. 13.9-ml of sodium hydroxide solution are required to reach the equivalence point, what is the normality,N, of sodium hydroxide? KHC8H4O4's equivalent weight is 204.2g/equiv and a 0.294g sample of an unknown acid requires 13.4-ml of 0.132N N

### Basic Techniques in Cell Biology and Biochemistry

The only problems that need to be done are numbers (3) and (4) on the second scanned document and the question below . Numbers (1), (2), (5) are finished problems that do not need to be done so problems (3) and (4) should be done using the same format (do Calculations and preparation)as those. Also please answer this ques

### Simple Chemistry Questions Relating Avogadro Number and Ph

i) What is the mass of 1.00 mol of CH2Cl2? ii) How many atoms of sodium are there in 1.00 mol of sodium? iii) How many hydrogen atoms are there in 3.75 mol methane (CH4)? iv) Give an example of a physical change involving colors.

### pH of a mixture of .001M sodium bicarbonate dissolved in water

How do you go about calculating the pH of .001M sodium bicarbonate (NaCO3) dissolved in water.....I some how derived the right answer which is pH = 8.3 but really have no idea how /i actually got the answer. How would I go about deriving the amount of [H+] so that I could use the equation [H+] = -log(???) = pH = 8.3

### pH and Molarity

Please help with the following problems. a.) Giving the reason for your answer, which would you expect to have the higher value of pH, a 1.0M solution of the strong acid, HCl or a 1.0M solution of the weak acid, acetic acid, CH3COOH? b.) Why is it that we can say that ozone in the stratosphere is beneficial to

### Particulates, Concentration and Combining Substances

a) A water sample contains 0.0700 grams of arsenic in 10.0L of water. What is the concentration of the arsenic in parts per million (ppm)? b) If a person breathes in 22m3 of air per day and the air contains 0.205 milligrams of particulates per m3 how many grams of particulates does the person breathe in per day? c) Expl

### Stoichiometry Problems, Limiting Reagent, Acid/Base, Balancing Chemical Equations

1. A solution is prepared by dissolving 10.8g ammonium sulfate in enough water to make 100.0mL of stock solution. A 10.00mL sample of this stock solution is added to 50.00mL of water. Calculate the concentration of ammonium ions and sulfate ions in the final solution. 2. One of the most commonly used white pigments in paint

### Quantative Analysis of Acid in Vinegar

Acid content of vinegar Flask 1 Flask 2 Inital volume of NaOH in burette 0 17.5 Final volume of NaOH in burette 17.5 35.3 Volume of NaOH used for titration

### Zn(OH)2 is amphoteric. In which of the following solutions

Zn(OH)2 is amphoteric. In which of the following solutions would the solubility of Zn(OH)2 be lowest and why? a) pure water b) 1 M ZnCl2 C) 1 M NH3 d) 1 M NaOH e) 1 M HCI

### PH OF A BASIC SOLUTION.

PH OF A BASIC SOLUTION. PH is defined as the negative logarithm of Hydrogen ion concentration. Strength of a base is expressed as the concentration of OH- ions. Therefore PH of a basic solution can be calculated using the relation Kw=[H+][OH-]=1x10-14 at 25degree celcius PH=-log[H+] Problem: Calculate the PH of a s

### Acid Base Reaction and Oxidation Numbers

1) Pennies made after 1982 contain 97% zinc by mass. A student wants to prove this by filing the copper outside the penny until he sees zinc and then putting the penny in a 1.00 M HCl solution. The zinc will be oxidized and the H+ (from the HCl) will be reduced: Zn + 2H+ ----- Zn2+ + H2 If the entire pen

### Calculations for Acid-Base Reactions

1) Given the following two equations, determine the number of grams of manganese dioxide required to prepare enough chlorine gas to produce 25.0 g of potassium hypochlorite. MnO2 + 4HCl ----- MnCl2 + Cl2 + 2H2O Cl2 + 2KOH ------ KCl + KClO + H2O 2) A titration is done us

### Molecular, Complete Ionic, and Net Ionic Equations

Write the molecular, complete ionic, and net ionic equations for the reactions that occur, if any, when solutions of the following substances are mixed: a.) nitric acid and barium carbonate b.) zinc chloride and lead nitrate c.) acetic acid and sodium hydroxide d.) calcium nitrate and sodium carbonate e.) ammonium chlorid