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Materials list

100 mls volumetric flask

3M hydrochloric acid (HCl) solution

sodium bicarbonate NaHCO 3 size 12{ left ("NaHCO" rSub { size 8{3} } right )} {}

methyl orange indicator

Part 2

  • Ask you TA for your assigned molarity–it will range from 0.7 M to 1.2 M.
  • First need to know the formula for the solute.
  • Need the molecular weight of the solute in g/mole.
  • The volume of solution, 100 mLs.
  • Remember to ensure that all the solute is dissolved before finally filling with deionised water to the mark on the volumetric flask.
  • Take your solution to your TA to check the molarity by titration, record value on your report form and your percent error.

Pre-lab 2: stoichiometry

(Total 10 points)

Click here to print the Pre-Lab Note: In preparing this Pre-Lab 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__________________________

Circle the correct answer:

1) Which one of the following is a correct expression for molarity?

A) mol solute/L solvent

B) mol solute/mL solvent

C) mmol solute/mL solution

D) mol solute/kg solvent

E)μmol solute/L solution

2) What is the concentration (M) of KCl in a solution made by mixing 25.0 mL of 0.100 M KCl with 50.0 mL of 0.100 M KCl?

A) 0.100

B) 0.0500

C) 0.0333

D) 0.0250

E) 125

3) How many grams of CH 3 OH size 12{"CH" rSub { size 8{3} } "OH"} {} must be added to water to prepare 150 mL of a solution that is 2.0 M CH 3 OH size 12{"CH" rSub { size 8{3} } "OH"} {} ?

A) 9.6× 10 3 size 12{"10" rSup { size 8{3} } } {}

B) 4.3× 10 2 size 12{"10" rSup { size 8{2} } } {}

C) 2.4

D) 9.6

E) 4.3

4) The concentration of species in 500 mL of a 2.104 M solution of sodium sulfate is __________ M sodium ion and __________ M sulfate ion.

A) 2.104, 1.052

B) 2.104, 2.104

C) 2.104, 4.208

D) 1.052, 1.052

E) 4.208, 2.104

5) Oxalic acid is a diprotic acid. Calculate the percent of oxalic acid H 2 C 2 O 4 size 12{H rSub { size 8{2} } C rSub { size 8{2} } O rSub { size 8{4} } } {} in a solid given that a 0.7984 g sample of that solid required 37.98 mL of 0.2283 M NaOH for neutralization.

A) 48.89

B) 97.78

C) 28.59

D) 1.086

E) 22.83

6) A 31.5 mL aliquot of H 2 SO 4 size 12{H rSub { size 8{2} } "SO" rSub { size 8{4} } } {} (aq) of unknown concentration was titrated with 0.0134 M NaOH (aq). It took 23.9 mL of the base to reach the endpoint of the titration. The concentration (M) of the acid was __________.

A) 0.0102

B) 0.0051

C) 0.0204

D) 0.102

E) 0.227

7) What are the respective concentrations (M) of Fe 3 + size 12{"Fe" rSup { size 8{3+{}} } } {} and I size 12{I rSup { size 8{ - {}} } } {} afforded by dissolving 0.200 mol FeI 3 size 12{"FeI" rSub { size 8{3} } } {} in water and diluting to 725 mL?

A) 0.276 and 0.828

B) 0.828 and 0.276

C) 0.276 and 0.276

D) 0.145 and 0.435

E) 0.145 and 0.0483

8) A 36.3 mL aliquot of 0.0529 M H 2 SO 4 size 12{H rSub { size 8{2} } "SO" rSub { size 8{4} } } {} (aq) is to be titrated with 0.0411 M NaOH (aq). What volume (mL) of base will it take to reach the equivalence point?

A) 93.6

B) 46.8

C) 187

D) 1.92

E) 3.84

9) A 13.8 mL aliquot of 0.176 M H 3 PO 4 size 12{H rSub { size 8{3} } "PO" rSub { size 8{4} } } {} (aq) is to be titrated with 0.110 M NaOH (aq). What volume (mL) of base will it take to reach the equivalence point?

A) 7.29

B) 22.1

C) 199

D) 66.2

E) 20.9

10) A solution is prepared by adding 1.60 g of solid NaCl to 50.0 mL of 0.100 M CaCl 2 size 12{"CaCl" rSub { size 8{2} } } {} . What is the molarity of chloride ion in the final solution? Assume that the volume of the final solution is 50.0 mL.

A) 0.747

B) 0.647

C) 0.132

D) 0.232

E) 0.547

Report 2: stoichiometry

(Total 80 points)

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). This is only an advisory template of what needs to be include in your complete lab write-up.

Name(Print then sign): ___________________________________________________

Lab Day: ___________________Section: ________TA__________________________

Part 1

Data table

Mass Grams
empty 150-mL beaker
NaHCO 3 in beaker size 12{"NaHCO" rSub { size 8{3} } " in beaker"} {}
Mass of NaHCO 3 size 12{"Mass of NaHCO" rSub { size 8{3} } } {}
Mass Grams
NaCl plus beaker first weighing
NaCl plus beaker second weighing
NaCl plus beaker third weighing

1) The grams of NaHCO 3 size 12{"NaHCO" rSub { size 8{3} } } {} you had in your beaker was ________

2) Calculate how many moles of NaHCO 3 size 12{"NaHCO" rSub { size 8{3} } } {} the mass is ________

3) Write the molar ratio for the NaHCO 3 size 12{"NaHCO" rSub { size 8{3} } } {} / NaCl ratio _______

4) Write the number of moles of NaCl you predict were produced in your experiment.

5) Calculate the mass of NaCl you predict will be produced.

6) Determine, by subtraction, the actual mass of NaCl produced in your experiment.

a) first weighing

b) second weighing

c) third weighing

7) Calculate your percentage yield.

Discussion questions

1. Compare the numerical value of the observed ratio for maximum yield to the best ratio

Part 2

Record your TAs value of the molarity of your solution.

Calculate your percent error from your assigned value.

Complete the equation for the titration of

NaHCO 3 aq + HCl aq size 12{"NaHCO" rSub { size 8{3 left ("aq" right )} } +"HCl" rSub { size 8{ left ("aq" right )} } rightarrow } {}

Questions & Answers

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In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
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Source:  OpenStax, Honors chemistry lab fall. OpenStax CNX. Nov 15, 2007 Download for free at http://cnx.org/content/col10456/1.16
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