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Acids and Bases

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

Solving for the products of reactions

(See attached file for full problem description) --- 1. Fe²+ and Sb³- 2. Mg²+ and As³- 3. Al³+ and O²- 4. Co³+ and I- 5. Sr² + and P³- 6. Ca²+ and C4+ 7. Fe³+ and As³- 8. Na + and S² ˉ Write the name or formula for these compounds: 1. tin (II) acetate 2. bromous acid 3. copper(II) permanganate

Chemistry Ka and Kb problems

1. Butyric acid is responsible for the odor in rancid butter. It has one weakly acidic proton. A solution of .25 M butyric acid has a pH of 2.71. Determine the Ka of the acid. 2. Ka for HCN is 4.0 x 10^10. Calculate Kb for CN. 3. For the equilibrium, CH3OH (g) <-- --> CO (g) + 2 H2, Kc is 6.9 x 10-2. At equilibriu

Solubility Problems with Ksp

Q#1 (Common ion problem) What is the solubility,in mg/mL of BaF2 in a)Pure Water b)in a solution containing 5.0mg/mL of KF Ksp of BaF2=1.0*10^-6 Q#2 Effect of pH on solubility a)Calculate the solubility of a saturated solution og Mg(OH)2 on pure water.(My answer is 1.65096*10^-4M b)Calculate the solubility of the sa

Applications of Aqueous Equilibria

50.00 mL of a 1.00 M solution of the diprotic acid H2A (Ka1= 1.0 * 10^-6 and Ka2 = 1.0 * 10^-10) is being titrated with 2.00 M NaOH . How many mL of 2.00 M NaOH must be added to reach a pH of 10?

Additive Eq

Using Hess' Law of additive equations, rearrange and/or multiply the following reactions in order to find the enthalpy for the radical reaction between hydrochloric acid and isopropyl alcohol (CH3CHOHCH3) to form water and isopropyl chloride. The dots you see indicate a radical, which is much different than an ion or an element

Solubility and Titration

(See attached file for full problem description) --- 1. Tooth enamel consists of hydroxyapatite, Ca5(PO4)3OH (Ksp = 6.8x10-37). Fluoride ion added to drinking water reacts with Ca5(PO4)3OH to form the more tooth decay-resistant fluorapatite, Ca5(PO4)3F (Ksp =1.0x10-60). Fluoridated water has dramatically decreased cavities

Lab experiment titrating hydrochloric and acetic acids with NaOH

I would like to see the details of the calculations. For my lab experiment I have the following data: Titration 1: 25.00mL of unknown concentration HCl 2 drops of phenolpthalein to show end-point 1.0M NaOH What is the molarity of the HCl? What is the Ka of the HCl? What is the equivalence point? What is the half-equival

pH Effect on Solubility & Expressions

3. Why does pH affect the solubility of CaF2 but not CaCl2? 4. Write the correct expression for Ksp for Al(OH) 3. (See attached file for full formatting)

pH After Titrations - Ionic Equilibria

1. Calculate the pH after 25.0 mL of .20 M HF (Ka=6.8 10-4) are titrated with 15.0 mL of .10 M NaOH? 2. Calculate the pH after 25.0 mL of 2.0 M HF is titrated with 50.0 mL of 1.0 M NaOH?

Titration Calculations

Note: You may assume that the densities of all solutions are 1.00 g/mL unless stated otherwise 1. A 10.00-mL sample of a solution containing the weak acid, formic acid, was placed in a 25-mL volumetric flask and diluted to the mark with water. A 10.00-mL sample of the diluted formic acid solution was then titrated with 0.13

Using Titration Techniques

1. If a strong acid and weak acid have the same concentration of acid, explain why they will have a different pH. 2. Explain why it is important to prime the pipette. 3. When using the titration technique explain why the beakers that contain the acid solutions must be dry before the acid is added, but the volumetric flask


(See attached file for full problem description) 3. Calculate the pH of 0.25 M HOAc. 4. Calculate Kb for OAc- .

Solubility Characteristics of Carboxylic Acids

1) If you took a pea-sized amount of salicylic acid and added 2 mL of demineralized water, what would the solubility of salicylic acid in the water be? 2) If you then added 5 drops of 6 M NaOH to the mixture, what would the solubility of salicylic acid in a base be? 3) I know the result of this is sodium salicylate, whi

Calculating pH Levels

Can someone please explain to me the following question? "Calculate the pH of a 1.0 M CH3COOH solution." My answer: pH = -log[H+] = -log[1.0] = 0 But how can that be right? Since CH3COOH is a weak acid, how can it have a pH of zero? Did I do something wrong?

Mol/Mol Calculation: Detailed Solution

How many milliliters of 3.00 M hydrochloric acid would be needed to react completely with a milk of magnesia tablet that contains 310 mg of Mg(OH)2? The neutralization reaction produces magnesium chloride, MgCl2, and water.

Percent yield

For the reaction SO3 + H2O yields H2SO4, calculate the percent yield if 500.g of sulfur trioxide react with excess water to produce 575 g of sulfuric acid? 82.7%, 88.3%, 91.2%, 93.9%

Titration: Sulfuric Acid

You are going to titrate sulfurous acid, H2SO3 (Ka1 = 1.7x 10minus 2 and Ka2 = 6.4 x 10 minus 8) with a 0.2000 M NaOH solution. If you start with 100 ml of 0.1275 M sulfurous acid, what is the initial pH? What is the pH of the solution at the first equivalence point? What is the pH at the second equivalence point? What is th