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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

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

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 ←→ Fe(H2O)36+ b) BF3 + NH3 ←→ F3BNH3 c) BF3 + F- ←→ 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) → __Ca3(PO4)2(s) + __NaCl(aq) 3. How many moles of calcium metal react to yield 0.50

PH, pOH

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

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

Formation of 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?

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

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

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

PH

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

What is the limiting reagent? Questions about chemical reactions

Please show how to solve the following questions: 2Al (s) + 2KOH (aq) + 4 H2SO4 (aq) + 22 H2O (l) --> 2KAl (SO4)2*12H2O (s) + 3H2 (g) 12.0 g of Al, 420 mL 2.0M KOH, 216 mL H2SO4 placed in 300 mL ice bath (water in excess) 1) What is the limiting reagent? 2) How much aluminum is necessary to produce 18g of alum? 3)

Balancing a Chemical Equation for Acid Reactions

Write a balanced chemical equation, include states of matter: 5 drops 0.1M MgSO4 to 5 drops of 0.1M BaCl2 Write a balanced chemical equation, include states of matter: 2 mL saturated Na2CO3 solution to 5 drops of 6M HCl

Balanced equations for different reactions

1) Write a balanced chemical equation, include states of matter: 5 drops of 0.1 M NaCl solution to 5 drops 0.1 M AgNO3 solution 2) Write a balanced chemical equation: About 10 drops of 6M NH3 to the AgCl formed in (1) (which dissolves the AgCl) 3) Write a balanced chemical equation: About 10 drops of 3M HNO3 to the p

Reaction between aluminum hydroxide and sulfuric acid

Solid aluminum hydroxide Al(OH)3 (s) reacts with aqueous sulfuric acid H2SO4 (aq) to produce aluminum sulfate Al2(SO4)3 (aq) and water. We combine 30.0g of Al(OH)3 (s) and 75.0 ml of 2.00 M H2SO4 (aq), and the reaction goes to completion. Subsequent analysis reveals that 12.3 g of Al2(SO4)3 was formed. What is the percent yield

Citric Acid and Fertilizer

Problem 1: Citric acid is concentrated in citrus fruits and plays a central metabolic role in nearly every animal and plant cell. How many moles of citric acid are in 1.90 qts of lemon juice *d=1.09 g/ml* that is 6.62% citric acid by mass? Problem 2: Nitrogen *N*, phosphorus *P*and potassium *K* are the main nutrients

Gas Laws and Stochiometry

1. How many significant figures does the sum of the following contain? 8.520 + 2.7? 2. How many moles of oxygen atoms are there in 10 moles of KCIO3? 3. The oxidation number of N in NaNo3 is? 4. What element is oxidized in the following chemical reaction? 3Cu + 8HNO3 ----> Cu(NO3) + 2NO + 4H2O 5. At what temp. will

Volume of Sulfuric Acid

What volume of 16 M sulfuric acid must be used to prepare 1.5 L of a 0.1 M sulfuric acid? a. 9.4 mL solution b. 9.4 L solution c. 16 mL solution d. 16 L solution