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Choose an input, click on the red box that corresponds to the port that your conductivity sensor is connected to. Choose 20,000 microseconds

“Choose a Sensor”, click radial button that says Conductivity Probe. Click next.

Click“Perform New Calibration”

Click“Add Calibration Point”place the conductivity probe in the non-conductive standard solution, while swirling wait until the value is constant and then enter 0.0 into the“Actual Value”box in MicroLab and hit“ok”.

Again, Click“Add Calibration Point”place the conductivity probe in the conducting standard solution, while swirling wait until the value is constant and then enter 1020 into the“Actual Value”box in MicroLab and hit“ok”. Repeat for 3860 as the Actual Value.

Under Curve Fit Choices , click on“First order (linear)”and then“Accept and Save this Calibration”, when prompted to“Enter the units for this calibration”, leave as is and click ok, save as your name-experiment-date. Click finish.

In the sensor area, left click on the conductivity icon and drag it to the Y-axis over“data source two”, also click and drag to column B on the spreadsheet and also click and drag to the digital display window.

When ready to obtain data, click start.

This is very important: Be sure to thoroughly since the probe with DI water between every use.

Beginning with the tap water, measure the conductance of each of the following solutions. Using the information provided in the lab manual, classify each solution as a non-, weak, or strong electrolyte. For those solutions that are electrolytes, record the ions present in solution.

Part iii. electrolyte strength and reaction rate

Chemicals

  • calcium carbonate powder - shake once
  • 1 M HCl - stopper it
  • 1 M HC 2 H 3 O 2 size 12{"HC" rSub { size 8{2} } H rSub { size 8{3} } O rSub { size 8{2} } } {}
  • 0.5 M H 2 SO 4 size 12{H rSub { size 8{2} } "SO" rSub { size 8{4} } } {} begin time
  • Test tube gas collection apparatus - end at 20mL

Measure 2 g of powdered calcium carbonate ( CaCO 3 size 12{"CaCO" rSub { size 8{3} } } {} ) onto a piece of weigh paper. Obtain 30 mL of 1 M HCl in a graduated cylinder. Pour the acid into the test tube apparatus. Add the calcium carbonate to the acid and QUICKLY stopper the tube to begin collecting gas. Record the time it takes to collect 20 mL of gas. The acid may react very fast with the CaCO 3 size 12{"CaCO" rSub { size 8{3} } } {} generating the gas very rapidly. Clean out the test tube apparatus and repeat the experiment using 1 M HC 2 H 3 O 2 size 12{"HC" rSub { size 8{2} } H rSub { size 8{3} } O rSub { size 8{2} } } {} and 0.5 M H 2 SO 4 size 12{H rSub { size 8{2} } "SO" rSub { size 8{4} } } {} .

Part iv. chemical reactions

Chemicals

  • 0.01 M calcium hydroxide, Ca ( OH ) 2 size 12{"Ca" \( "OH" \) rSub { size 8{2} } } {}
  • Plastic straws

Obtain ~20 mL of saturated calcium hydroxide solution. Make sure it is clear and colorless. Place the conductivity probe in the solution and begin monitoring it conductivity. With your straw, slowly exhale into the solution. Note any observations in the solution and the conductivity.

Pre-lab 5: bonding 07

(total 10 points)

Hopefully here for the Pre-Lab

Name(Print then sign): ___________________________________________________

Lab Day: ___________________Section: ________TA__________________________

This assignment must be completed individually and turned in to your TA at the beginning of lab. You will not be allowed to begin the lab until you have completed this assignment.

Part i. bonding of chemicals in solution

  • Write out the formulas of the following acids:
  • phosphoric ____________________
  • perchloric ____________________
  • nitric ____________________
  • sulfuric __________________
  • hydrochloric ____________________
  • acetic ____________________
  • Write out the formulas of the following bases:
  • calcium hydroxide ____________________
  • potassium hydroxide ____________________
  • sodium hydroxide ____________________
  • ammonia ____________________
  • Write out the formulas of the following salts:
  • potassium chromate ____________________
  • potassium sulfate ____________________
  • copper(II) nitrate ____________________
  • calcium carbonate ____________________
  • potassium iodide ____________________

Report 5: bonding 07

Hopefully here for the Report Form

Note: In preparing this report you are free to use references and consult with others. However, you may not copy from other students’work (including your laboratory partner) or misrepresent your own data (see honor code).

Name(Print then sign): ___________________________________________________

Lab Day: ___________________Section: ________TA__________________________

Part i. predicting bond type through electronegativity differences.

Chemical Formula Electroneg (1) Electroneg (2) Diff Electroneg Type of bond
KCl
CO
CaBr 2 size 12{"CaBr" rSub { size 8{2} } } {}
SiH 4 size 12{"SiH" rSub { size 8{4} } } {}
MgS

Part ii. weak and strong electrolytes

Solution Tested Numerical Output Electrolyte Strength Ions Present
0.1 M HCl
0.1 M HC 2 H 3 O 2 size 12{"HC" rSub { size 8{2} } H rSub { size 8{3} } O rSub { size 8{2} } } {}
0.1 M H 2 SO 4 size 12{H rSub { size 8{2} } "SO" rSub { size 8{4} } } {}
0.1 M NaOH
0.1 M NH 3 size 12{"NH" rSub { size 8{3} } } {}
0.1 M NaC 2 H 3 O 2 size 12{"NaC" rSub { size 8{2} } H rSub { size 8{3} } O rSub { size 8{2} } } {}
0.1 M NaCl
0.1 M NH 4 C 2 H 3 O 2 size 12{"NH" rSub { size 8{4} } C rSub { size 8{2} } H rSub { size 8{3} } O rSub { size 8{2} } } {}
0.1 M NH 4 Cl size 12{"NH" rSub { size 8{4} } "Cl"} {}
CH 3 OH size 12{"CH" rSub { size 8{3} } "OH"} {}
C 2 H 5 OH size 12{C rSub { size 8{2} } H rSub { size 8{5} } "OH"} {}
Sucrose
Tap water

1. Why do we use deionized water instead of tap water when making solutions for conductivity measurements?

Part iii. electrolyte strength and reaction rate

2. Time to collect 20 mL of gas using 1 M HCl _______________________. Write the reaction of HCl with CaCO 3 size 12{"CaCO" rSub { size 8{3} } } {} .

3. Time to collect 20 mL of gas using 1 M HC 2 H 3 O 2 size 12{"HC" rSub { size 8{2} } H rSub { size 8{3} } O rSub { size 8{2} } } {} _______________________. Write the reaction of HC 2 H 3 O 2 size 12{"HC" rSub { size 8{2} } H rSub { size 8{3} } O rSub { size 8{2} } } {} with CaCO 3 size 12{"CaCO" rSub { size 8{3} } } {} .

4. Time to collect 20 mL of gas using 0.5 M H 2 SO 4 size 12{H rSub { size 8{2} } "SO" rSub { size 8{4} } } {} _________________________.Write the reaction of H 2 SO 4 size 12{H rSub { size 8{2} } "SO" rSub { size 8{4} } } {} with CaCO 3 size 12{"CaCO" rSub { size 8{3} } } {} .

5. Why does it take different lengths of time to collect 20 mL of gas?

6. Based on the time it took to collect 20 mL of gas, rank the acids in the order of increasing strength.

7. Why did we use 0.5 M H 2 SO 4 size 12{H rSub { size 8{2} } "SO" rSub { size 8{4} } } {} instead of 1.0 M H 2 SO 4 size 12{H rSub { size 8{2} } "SO" rSub { size 8{4} } } {} ?

Part iv. chemical reactions

8. Write the chemical reaction for calcium hydroxide with your exhaled breath.

9. Write your observations for the reaction that took place (i.e. appearance, conductivity, etc.)

10. When in separate solutions, aqueous ammonia, NH 3 size 12{"NH" rSub { size 8{3} } } {} (aq) and acetic acid HC 2 H 3 O 2 size 12{"HC" rSub { size 8{2} } H rSub { size 8{3} } O rSub { size 8{2} } } {} conduct electricity equally well. However, when the two solutions are mixed a substantial increase in electrical conductivity is observed. Explain.

11. Separately, ammonium sulfate and barium hydroxide solutions are very good conductors. When the two solutions are mixed a substantial decrease in conductivity is observed. Rationalize this.

Questions & Answers

what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
Daniel
Researchers demonstrated that the hippocampus functions in memory processing by creating lesions in the hippocampi of rats, which resulted in ________.
Mapo Reply
The formulation of new memories is sometimes called ________, and the process of bringing up old memories is called ________.
Mapo Reply
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Source:  OpenStax, Gen chem lab. OpenStax CNX. Oct 12, 2009 Download for free at http://cnx.org/content/col10452/1.51
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