Loading...

Messages

Proposals

Stuck in your homework and missing deadline? Get urgent help in $10/Page with 24 hours deadline

Get Urgent Writing Help In Your Essays, Assignments, Homeworks, Dissertation, Thesis Or Coursework & Achieve A+ Grades.

Privacy Guaranteed - 100% Plagiarism Free Writing - Free Turnitin Report - Professional And Experienced Writers - 24/7 Online Support

Experiment a5 evidence for chemical change answer key

06/01/2021 Client: saad24vbs Deadline: 10 Days

Copyright 2019 - Hands-On Labs | http://holscience.com 1 / 10


Student Name


Mohammed Alnaimi


Student ID 48408 Lesson Observations of Chemical Changes Institution Ocean County College Session 2019L2 CHEM 181 DL1 Course CHEM 181 DL1 Instructor Lea Stage


Final Report


Exercise 1


CHEM 181 DL1 Observations of Chemical Changes


I would drop in some hydrochloric acid and see if the household product fizzes and releases gas. If so, it most likely has sodium bicarbonate in it.


1. Suppose a household product label says it contains sodium hydrogen carbonate (sodium bicarbonate). Using your results f rom Data Table 1 as a guide, how would you test this material f or the presence of sodium bicarbonate?


AgNO3 (aq) + NaOH (aq) ------> AgOH (s) + NaNO3 (aq)


2. Write the chemical equation for the reaction in well A6.


Copyright 2019 - Hands-On Labs | http://holscience.com 2 / 10


This reaction occurred in A1 I believe. That was the only reaction that caused any type of fizzing or gas, which would be the CO .


3. One of the reactions you observed resulted in these products: NaCl + H O + CO (g)? What well did this reaction occur in? Describe how the observations for this reaction support your answer.


2 2


2


I would believe that the substance is actually sodium hydroxide. Vinegar is made up to acetic acid, and according to my table, phenolphthalein does not cause acids to turn pink.


4. You found a sample of a solution that has a f aint odor resembling vinegar (an acid). To verif y that it is vinegar, you add a few drops of phenolphthalein. T he sample turns pink. From this result, can you assume this sample is indeed vinegar or contains some vinegar? Explain your answer using your results f rom Data Table 1.


I would assume that the fifth cookie does not have as much starch as the other cookies. The starch has not been removed completely, but is in a lesser quantity than the others.


5. While performing a starch test on several dif f erent cookie brands, f our tests result in the typical black color of starch presence, but the f if th gives a yellow-brown color. How might you interpret this result?


I would drop some of the hair tonic into some potassium iodide. If the substance begins to turn yellow, there is some lead in the tonic


6. You have read that a new brand of hair tonic is supposed to contain lead (an ingredient in Grecian Formula ). Devise a simple test to conf irm the presence or absence of lead in that hair tonic. Use your observations in Data Table 1 to describe a posit ive result f or this test.


®


Copyright 2019 - Hands-On Labs | http://holscience.com 3 / 10


Data Table 1: Chemical Change Observations


I believe that this is the result of a chemical change. When the chemicals in the soda mix with the air while being poured into the glass, a gas is released. That gas causes the bubbles and fizzing.


7. Is cutting a cake into 8 pieces a chemical or a physical change? Explain your answer.


I believe that this is the result of a chemical change. When the chemicals in the soda mix with the air while being poured into the glass, a gas is released. That gas causes the bubbles and fizzing.


8. When a soda is poured into a glass and the soda bubbles, is it the result of a chemical change? Explain your answer.


In the second step, the reactant was the direct sunlight. This is a chemical reaction because it turned the color of dark brown similar to rust on the paper towel


9. In well B1, what was the reactant in the second step? Did this reactant cause a chemical change? Use your observations to support your answer.


Phenolphthalein acts well as an acid/base indicator. The reactions in A5 definitely support this statement. Sodium hydroxide is a base and hydrochloric acid is an acid. So, according to the table, phenolphthalein causes bases to turn pink and acids to remain clear.


10. T hink about how phenolphthalein acts as an acid/base indicator. Do your observations in well A5 support this or contrast what you would expect to happen? Explain your answer.


Well Chemical #1 (4 drops)


A1 NaHCO Sodium Bicarbonate3


Copyright 2019 - Hands-On Labs | http://holscience.com 4 / 10


A2 IKI indicator


A3 KI Potassium Iodide


A4 NaOH Sodium Hydroxide


A5 HCl Hydrochloric Acid


A6 NaOH Sodium Hydroxide


B1 AgNO Silver Nitrate


B2 NH OH Aqueous Ammonia


Well Chemical #1 Appearance


A1


A2


A3


A4


A5


A6


B1


B2


Well Chemical #2 (4 drops)


A1 HCl Hydrochloric Acid


A2 Starch


A3 Pb(NO ) Lead(II) Nitrate


A4 C H O Phenolphthalein


A5 C H O Phenolphthalein


A6 AgNO Silver(II) Nitrate


B1 NH Aqueous Ammonia


B2 CuSO Copper(II) Sulfate


3


4


no color, liquid


no color, liquid


no color, liquid


no color, liquid


no color, liquid


no color, liquid


no color, liquid


no color, liquid


3 2


20 14 4


20 14 4


3


4


4


Copyright 2019 - Hands-On Labs | http://holscience.com 5 / 10


Well Chemical #2 Appearance


A1


A2


A3


A4


A5


A6


B1


B2


Well Observations


A1


A2


A3


A4


A5


A6


B1 Observation 1:


+ Absorb in paper towel and expose to sunlight Observation 2:


B2


no color, liquid


no color, liquid


no color, liquid


no color, liquid


no color, liquid


no color, liquid


no color, liquid


light blue


No color change, bubbling and fizz ing occurred


blue-black color


yellow


Became bright pink


No Change


light brown, black starches


Became white and cloudy


Became a brown, rusty color


blue


Copyright 2019 - Hands-On Labs | http://holscience.com 6 / 10


Exercise 2


Well Chemical Change (Yes/No)


A1


A2


A3


A4


A5


A6


B1


B2


Yes


Yes


Yes


Yes


No


Yes


Yes


Yes


For the magnesium, both reactions produced a chemical change, resulting in the metal burning and turning to ash. The main difference in the two reactions came down to burning it. When directly over a flame, the magnesium bursts into a bright white light, whereas in the test tube it just glowed red and turned into ashes.


1. Describe the similarit ies and/or dif f erences between heating and burning the magnesium metal. Did either heating or burning produce a chemical change? Explain your answer using the observations collected in Data Table 2.


Copyright 2019 - Hands-On Labs | http://holscience.com 7 / 10


I did not observe any differences between the heating and burning of the zinc. Both methods caused the zinc to heat up and melt into a liquid. Even when I kept the zinc over the flame after melting, no type of chemical reaction occurred.


2. Describe the similarit ies and/or dif f erences between heating and burning the mossy zinc metal. Did either heating or burning produce a chemical change? Explain your answer using the observations collected in Data Table 2.


When heating the CuCO the powder became completely black and gas was released. There was no reaction after that. When burning the chemical, the powder still turned black but (I assume) the gas that was released caused the flame to glow bright blue.


3. Describe the similarit ies and/or dif f erences between heating and burning the Cu(NO ) . Did either heating or burning produce a chemical change? Explain your answer using the observations collected in Data Table 2.


3 2


3,


The heating and burning of Cu(NO ) was exactly the same, other than the addition of the glowing flame when heated.


4. Describe the similarit ies and/or dif f erences between heating and burning the CuCO . Did either heating or burning produce a chemical change? Explain your answer using the observations collected in Data Table 2.


3


3 2


In this experiment, I learned that chemicals react in many ways when exposed to different things. Whether it is mixing two chemicals together or setting one on fire, the reactions differ based on the method that chemical was tested. I also learned that these chemical reactions could be very helpful when trying to identify the chemical makeup of items. You can learn exactly what a product might be made out of from watching the reaction it has with heat, air, or water.


5. How would you describe the dif f erences between heating and burning? Use your experiences in the experiment to describe these dif f erences.


Copyright 2019 - Hands-On Labs | http://holscience.com 8 / 10


Data Table 2: Heating and Combustion


The only chemical that has a physical change when heated was the mossy zinc. It melted and boiled in the test tube, but did not burn or change in color.


6. Which of the four chemicals that was heated produced a physical change? Support your answer with observations made and recorded in Data Table 2.


Copyright 2019 - Hands-On Labs | http://holscience.com 9 / 10


Chemical Initial Observations


Mg


Zn


CuCO


Cu(NO )


Chemical Heating Observations


Mg


Zn


CuCO


Cu(NO )


Chemical Burning Observations


Mg


Zn


CuCO


Cu(NO )


small, silver, shiny


large, rock-like, silver


3 fine sea-for green powder


3 2 salt-like blue crystals, compact


glowed bright red and became a white ash


melted into liquid


3 turned black


3 2 Melted and turned green, lots of fizz ing and gas released, then turned black


Glowed red, then turned into a bright white flame, then turned into ash


Melted into a liquid, glowed red


3 The flame glowed blue and the powder turned black


3 2 The flame glowed green, the crystals bubbled and turned black


Copyright 2019 - Hands-On Labs | http://holscience.com 10 / 10

Homework is Completed By:

Writer Writer Name Amount Client Comments & Rating
Instant Homework Helper

ONLINE

Instant Homework Helper

$36

She helped me in last minute in a very reasonable price. She is a lifesaver, I got A+ grade in my homework, I will surely hire her again for my next assignments, Thumbs Up!

Order & Get This Solution Within 3 Hours in $25/Page

Custom Original Solution And Get A+ Grades

  • 100% Plagiarism Free
  • Proper APA/MLA/Harvard Referencing
  • Delivery in 3 Hours After Placing Order
  • Free Turnitin Report
  • Unlimited Revisions
  • Privacy Guaranteed

Order & Get This Solution Within 6 Hours in $20/Page

Custom Original Solution And Get A+ Grades

  • 100% Plagiarism Free
  • Proper APA/MLA/Harvard Referencing
  • Delivery in 6 Hours After Placing Order
  • Free Turnitin Report
  • Unlimited Revisions
  • Privacy Guaranteed

Order & Get This Solution Within 12 Hours in $15/Page

Custom Original Solution And Get A+ Grades

  • 100% Plagiarism Free
  • Proper APA/MLA/Harvard Referencing
  • Delivery in 12 Hours After Placing Order
  • Free Turnitin Report
  • Unlimited Revisions
  • Privacy Guaranteed

6 writers have sent their proposals to do this homework:

Top Essay Tutor
Helping Hand
University Coursework Help
Writer Writer Name Offer Chat
Top Essay Tutor

ONLINE

Top Essay Tutor

I have more than 12 years of experience in managing online classes, exams, and quizzes on different websites like; Connect, McGraw-Hill, and Blackboard. I always provide a guarantee to my clients for their grades.

$40 Chat With Writer
Helping Hand

ONLINE

Helping Hand

I am an Academic writer with 10 years of experience. As an Academic writer, my aim is to generate unique content without Plagiarism as per the client’s requirements.

$35 Chat With Writer
University Coursework Help

ONLINE

University Coursework Help

Hi dear, I am ready to do your homework in a reasonable price.

$37 Chat With Writer

Let our expert academic writers to help you in achieving a+ grades in your homework, assignment, quiz or exam.

Similar Homework Questions

A porsche accelerates from a stop light - Walt disney company mission statement 2017 - Legal and ethical basis for advance directives - 85 area code country - Literary analysis paper - Parallel programming with mpi pacheco pdf - How to date a browngirl by junot diaz analysis - Executive mba abu dhabi - Geotechnical Earthquake hw assignment - Spiritual gifts test lifeway - Ibm opos configuration utility - Chapter 10 scarlet letter quotes - Assignment 3: Not All Companies Are Viewed as Equal - University of salford staff channel - Physics ib data booklet - Work near underground assets guideline - Project recommendation report - Molar mass of ammonium dichromate - NEED IN 15 HOURS or LESS - 6.8 billion in scientific notation - Aca code of ethics cultural competence - Project risk management case study questions and answers - Msd animal health upper hutt - Zinc and hydrochloric acid lab report - SOCW6446 WEEK 11 FINAL PROJECT - Training and Development - Are noble gases malleable - 10 basic tasks of the strategy execution process - Business and law - Graduation gear up ou - Acetic acid density g ml - If i had one wish - Axis m3014 default password - Rules of stage movement - Hunger games symbolism worksheet - Physical Geography Research Paper - How to write scientific report - Quantitative spectroscope and visible light lab - World Civilization before 1650. - 10/56 sloane street summer hill - Examples of bias in history textbooks - Speech of joseph mccarthy wheeling west virginia february 9 1950 - Parris in the crucible - What is the theme of the other wes moore - Stages of bleaching hair - Life stages nutrition presentation sci 220 - Managerial Finance paper - Political Science - Ingalls shipbuilding apprenticeship program - Radioactive dating game lab worksheet answers - Marketing excellence nike case study solution - What is extent of reaction - 36297 n gantzel rd ste 101 - 100 ml graduated cylinder sig figs - Malware Protection Procedure Guide - Virtual fetal pig dissection worksheet answers - Fill out study guide- nursing definitions - Motor grader productivity per hour - At the first psychological clinic the patients were primarily - Tickles deli menu erie pa - Business Finance Essay - Curse of the black stone rs3 - Square root of 75 - In a period of rising prices, the costs allocated to ending inventory may be understated in the - Inexact line search matlab - Investigation 5a air pressure change answers - Todos los turistas llegan a machu picchu en autobús - Organizational Economics - Partners healthcare case study harvard solution - Consistent carb diet foods - Consumer behavior building marketing strategy - OperationsManagementForLeaders_Assessment1 - Katerina ivanovna crime and punishment - English U2 W4 - The quantity of money demanded is the - Report 2 - English 101- Essay- 3 pages- MLA format- Due in hour - For Essays Guru - - What is the manufacturer-specific id for the gemtek radio transmitter/receiver? - Kpi examples contract management - Coolwipes case solution - Advanced pathophysiology practice questions - Who reconciled the feud between the townspeople and odysseus - Guide to operating systems 4th edition case project answers - Assignment: Executive Leadership Self-Assessment and Self-Development Plan - B46 28 gower street summer hill - Ilium neocort cream australia - Advantages of java virtual machine - Palo alto networks single pass architecture - Great gatsby chapter 3 summary - Three switches outside a windowless room - Physical Security practical connection - Shooting dad essay - Develop a plan to address the political, regulatory, or technological environments that impact organizations’ supply chain sustainability and strategies - School days according to humphrey - Cae adda campsite trawsfynydd - Three grams of musk oil are required for each - 15 grand strategies with examples - Stance essays on treating animals humanely - How to earn zora's trust outer worlds