EXPERIMENT: Add a 1/2 cup of vinegar and a teaspoon of table salt and stir. Drop...

EXPERIMENT: Add a 1/2 cup of vinegar and a teaspoon of table salt and stir. Drop 15 pennies into the solution for 10 to 15 minutes. Pull them out and allow them to dry by themselves on a towel. After setting them out for a while, the pennies should turn blue.

QUESTIONS

1. Vinegar is an acid that allowed the copper metal to be oxidized to copper (II) ion. Is copper metal becoming copper (II) ion an oxidation or a reduction? How do you know?

2. When pennies coated with copper (II) ion were renoved from the solution and set out in the air, the copper (II) ion on the penny combined with oxygen gas from the air to produce the blue product that you observed. What is the blue product? Write its formula.

3. Write the reaction showing copper (II) (aq) + oxygen gas -> blue product

Expert Solution

Pennies before cleaning looks dirty because copper ions react with oxygen to form Copper oxide which is dull/black colored. When acetic acid and salt(chloride) are used, the copper oxide layer is washed off and the pennies are cleaned.

a) In this reaction, Copper is converted to Cu⁺²

This is given by the equation : Cu ------------------> Cu⁺² + 2e^-

This is an oxidation reaction because the metal loses electrons and gets reduced and this reaction is termed as oxidation.

b) When Cu⁺² ions were removed and set out in the air without rinsing, the Cu⁺² ions on penny combine with oxygen from air and chlorine from salt to form a blue product called malachite

Formula of malachite is Cu₂CO₃(OH)₂ or CuCO₃.Cu(OH)₂. It is blue- greenish color

Cu⁺²_(aq)+ O_2(g)

Action of vinegar on copper(Cu) forms Copper acetate

Cu exists in +2 state in Copper acetate. Copper acetate is given by CH₃COOCu

2Cu + O₂ <------------> 2CuO

CuO + 2CH₃COOH -------------> Cu(CH₃COO)₂ + H₂O

2Cu(CH₃COO)₂ + O₂ -------------> CuCO₃.Cu(OH)₂

queen_honey_blossom answered 2 years ago

A recipe calls for 1 1/5 cups of flour for every 1/2 teaspoon of salt. Suppose...

A recipe calls for 1 1/5 cups of flour for every 1/2 teaspoon of salt. Suppose you put 4 cups of flour in a mixing bowl. How much salt should you add?

Material: Plant tissue (strawberries or split peas) 400-mL beaker Blender Table salt Tablespoon 1/8 teaspoon Liquid...

Material: Plant tissue (strawberries or split peas) 400-mL beaker Blender Table salt Tablespoon 1/8 teaspoon Liquid detergent Test tubes and test tube rack Meat tenderizer Glass rods Ice-cold 70–95% ethanol Ice-cold dH2O Strainer Procedure – DNA Extraction 1. Combine in a blender: 1/2 cup frozen green split peas or approx. 1/2 cup frozen strawberries 1/8 teaspoon table salt 1 cup cold (refrigerated or use ice to chill) water 2. Cover and blend on the high setting for 30 seconds. 3....

Substance Strong/Weak/Non Molecular/Ionic Ionize/Dissociate Tap Water Deionized Water Table salt Sucrose Vinegar Ethanol

1-D Kinematics Experiment 1: Free Fall In this experiment you will drop the hex nut from...

1-D Kinematics Experiment 1: Free Fall In this experiment you will drop the hex nut from different heights. You will explore how height from which the hex nut is dropped affects its falling time and its final velocity. Materials: Hex nut Stopwatch Tape Measure Procedure a) Write down a hypothesis how height will affect the falling time of an object. (Note: use form: if…… then……) b) Write down a hypothesis how height will affect final velocity of the falling object....

If you add a 1 cm3 (1 ml) cube of salt (density 2.16 g/cm3) to 10...

If you add a 1 cm3 (1 ml) cube of salt (density 2.16 g/cm3) to 10 ml of water (1 g/cm3) what is a reasonable total volume? If you add a 1 cm3 (1 ml) cube of salt (density 2.16 g/cm3) to 10 ml of water (1 g/cm3) what is a reasonable final density? If you add a 1 cm3 (1 ml) cube of salt (density 2.16 g/cm3) to 10 ml of water (1 g/cm3) what is a reasonable final...

in percentage of water in hydrated salts experiment 1.How does the “percent-water in the hydrated salt”...

in percentage of water in hydrated salts experiment 1.How does the “percent-water in the hydrated salt” will be affected -? a.If you handle the crucible with (oily) fingers before its mass measurements. . b.If the hydrated salt is overheated and the anhydrous salt thermally c.decomposes, one product being a gas d.If one student decided to skip the step of reheating the sample in the experimental procedure. e.If the original sample is unknowingly contaminated with a second anhydrous salt. 2. What...

Part 2: Use MySQL Workbench to add a table to your database on the class server...

Part 2: Use MySQL Workbench to add a table to your database on the class server and name the table “Person”. Include these fields in the Person table: Field Name Description Data Type Sample Value LoginID User’s login name varchar(10) Bob FirstName User’s first name varchar(50) Bob LastName User’s last name varchar(50) Barker picUrl Filename of the user’s picture varchar(50) bob.gif Bio User’s biography varchar(255) Bob is the best! LoginID should be the Primary Key of the table. Add at...

Experiment 2- Cloning a DNA Fragment to a Bacterially-Derived Plasmid Vector “Table 1: Fragment Lengths” “DNA...

Experiment 2- Cloning a DNA Fragment to a Bacterially-Derived Plasmid Vector “Table 1: Fragment Lengths” “DNA Type” “Longest Length (in base pairs)” “Foreign” 720 “Plasmid” 2804 1. What is the expected size of the plasmid plus the cut foreign DNA? 2. What type of ends to the enzymes BamHI and EcoRI produce? How does this type of end facilitate cloning? 3. What enzyme is necessary to permanently link the digested foreign and plasmid DNA together to form the recombinant DNA...

Data Table 1. Adding 0.1M HCl from D1 into A1. Drop Number pH of Solution 1...

Data Table 1. Adding 0.1M HCl from D1 into A1. Drop Number pH of Solution 1 5.0 2 5.0 3 5.0 4 5.0 5 5.0 6 5.0 7 5.0 8 5.0 9 5.0 10 5.0 11 5.0 12 5.0 13 5.0 14 5.0 15 5.0 Data Table 2. Adding 0.1M NaOH from D6 into A6. Drop Number pH of Solution 1 6.0 2 6.0 3 6.0 4 6.0 5 6.0 6 6.0 7 6.0 8 6.0 9 6.0 10 6.0...

A probability experiment is conducted in which the sample space of the experiment is {1, 2,...

A probability experiment is conducted in which the sample space of the experiment is {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12}, event F={4, 5, 6, 7, 8}, and event G={8, 9, 10, 11}. Assume that each outcome is equally likely. List the outcomes in F or G. Find P(F or G) by counting the number of outcomes in F or G. Determine P(F or G) using the general addition rule. List the outcomes in F...

Question