keighcazandraaquino241

Suppose that you transfer 10.00 mL of 0.1106 M HCL into anerlenmeyer flask via volumetric pipet. You then then add 25 mL ofdeionized water to the flask to dilute the acid solution
* moles present at begginning is 1.106 mL

- suppose you titrate this HCl solution with NaOH of an unknownconcentration. At the beginning of the titration, your initialvolume reading from the buret (Vi) is 0.52 mL.at the endpoint whenthe solution turns pink, the final burnet reading (Vf) is 14.16 mL.what is the total volume (in mL) of Naoh solution added to reachthe endpoint??

2. A 20.00 mL volume of an HA acid solution of unknown concentration with 2 drops of phenolphthalein requires 0.150 M NaOH was put in buret to reach the endpoint in the titration. The initial reading of NaOH is 5.5 mL and the final reading of NaOH in the buret is 22.5 mL.

0 out of 2 points

10.00 mL of the unknown H₂SO₄ solution is titrated with the standardized NaOH solution (you calculated the concentration of the NaOH in Question 5). The initial buret reading (V_i) at the beginning of the titration was 0.28 mL. The final buret reading (V_f) at the end of the titration was 37.08 mL. How many moles of NaOH were added to reach the endpoint?

.387 g of potassium hydrogen phthalate were titrated with sodium hydroxide. the initial reading on the buret was .48 mL, and the final reading on the buret was 21.03 mL. A) how many moles of potassium hydrogen phthalate were used in the titration? B) how many moles of sodium hydroxide reacted with potassium hydrogen phthalate? C) what volume of sodium hydroxide was used? D) what is the molarity of the sodium hydroxide solution and the normality?

A buret is filled with a 0.2005 M ( + or - 0.4%) solution of sodium hydroxide. At the beginning of a titration, the initial buret reading is 2.45 mL. After the end point of the titration is reached, the final buret reading is 42.06 mL.

a) How many moles of sodium hydroxide were delivered during this titration?

b) If the tolerance of the buret is (+ or - 0.6 mL) (applicable to each volume measurement), what is the absolute uncertainty associated with your answer to part a?

Show all work.

Consider the following hypothetical reaction:

A + 3B ⇄ 2C + D

A titration was performed in which a standardized solution of A was used as the titrant, and an unknown amount of B was the analyte. The concentration of A in the standardized solution was 0.2005 M (± 0.4%). The initial buret reading was 2.45 mL, and the final buret reading (at the endpoint) was 42.06 mL

a) How many moles of B were present in the unknown sample?

b) If the tolerance of the buret is ±0.06 mL, what is the absolute uncertainty associated with your answer to part A?

from the following reaction: A+3B-> 2C+D, A titration was performed where A was the titrant and unknown amounts of B were the analyte. The concentration of A in the solution is 0.2005M (+/-.4%). the initial buret reading is 2.45mL, and the final is 44.03mL. How many moles of B were present in the unknown sample? If the tolerance of the buret was +/- 0.06mL what is the absolute uncertainty?

A student dissolved 0.13 g of a sample containing an unkinown amount of cholride ion in 50 mL of water. She then added 6 drops of Na2CrO4 and titrated the solution using a 0.049 M solution of silver nitrate. She obtained the following data. Initial buret reading = 0.02 mLFinal buret reading = 21.46 mLa. What volune of tirant (silver nitrate, AgNo3) was used?b. How many moles of silver were added to the solution?c. How many moles of chloride were present in the unknown?d. What mass of cholride was present in the unknown?e. What was the mass percentage of cholride present int he original sample?Please show work.

Need help to find what is empty in this data/calculation page

Molarity if standard AgNO3 solution - 0.492 AgNO3 M

Mass of vial and chloride unkown - 24.1998 g

Mass of vial - 23.2177 g

Mass of unkown in volumetric flask - 0.9821 g

Mass of unknown in each 20.00-mL sample - ___g

Average Value of Percentage Cl^- in unknown: ______%

The links for the websites are provided on the picture.

1. What was the problem with Palestine after the First World War?

2. What organization proposed the division of Palestine into two independent states?

3. What did the Israelis use to force the maintenance of their territory?

4. What year were the Israel-PLO Oslo Accords signed?

1. Although there is no strict definition for Western culture, there are some commonalities found among countries who share Western culture. Please list 5 commonly shared features. 

2. How does culture influence morality? Please define morality and culture as part of your answer. 

3. Why was the United Nations created? What is the role of the UN? Describe the structure of the United Nations and give examples of issues that the UN is involved with. 

4. What is an NGO? Describe the purpose of NGOs and give at least 2 examples. 

Please help me with my midterm! Show solution if possible for better understanding. Thank you

Introduction to chemistry.

The following questions will test your ability to make inferences based on the given observations.

The following solutions are listed with their corresponding color:

Solution Color

Aluminum nitrate, Al(NO₃)₃(aq) colorless

Barium chloride, BaCl₂(aq) colorless

Calcium Chloride, CaCl₂(aq) colorless

Cerium (III) nitrate, Ce(NO₃)₃(aq) colorless

Cerium(IV) sulfate , Ce(SO₄)₂(aq) colorless

Chromium (III) chloride, CrCl₃(aq) blue green

Cobalt(II) chloride, CoCl₂(aq) red

Copper(II) chloride, CuCl₂(aq) light blue

Iron(III) chloride, FeCl₃(aq) light orange

Lead (II) nitrate, Pb(NO₃)₂(aq) colorless

Lithium chloride, LiCl (aq) colorless

Magnesium chloride, MgCl₂(aq) colorless

Nickel (II) chloride,NiCl₂ light green

Potassium chloride, KCl(aq) colorless

Silver Nitrate, AgNO₃(aq) colorless

Sodium Chloride, NaCl(aq) colorless

Tin(II) chloride, SnCl₂(aq) colorless

Tin(IV) chloride, SnCl₄(aq) colorless

Zinc Nitrate, Zn(NO₃)₂ colorless

Considering the metallic cation (the first symbol in the formula), what can be inferred from the color of the solutions. Indicate the classification of the metallic cation and give ihe correlation of the color of the solution and the type of the metal cation.

b.From the names of the compound in solution as indicated above, what can you conclude on how the systematic names are given?

The following chemical reactions were carried out and observations were recorded:

Three milliliters of 0.1M CaCl₂ were mixed with two mL of 0.1 m Na₃PO₄

Observation: Upon mixing the two solutions, a cloudy mixture formed

Write a balanced chemical equation and indicate which is the solid formed in the reaction.

What is the type of the chemical reaction?

A few drops of water was added to a test tube containing 0.5 g of anhydrous copper sulfate (CuSO₄) and the following observations were noted:

Anhydrous copper sulfate – light blue

Anhydrous copper sulfate plus water- sky blue

What can you conclude from the given observation?

Given that the formula of hydrated copper(II) sulfate is CuSO₄.5H₂O,write the chemical equation that shows the formation of copper(II) sulfate pentahydrate from the anhydrous form.

Classify the reaction.

To a small piece of zinc metal placed in a test tube, one milliliter of 3M HCl was added. Bubbling was noted and the test tube felt hot, and the metal disappeared after a few minutes.

What can be concluded from this experiment?

Write the balanced chemical equation and classify the reaction.

A test tube containing 0.5 g Cu(OH)₂ was heated using a Bunsen burner, and the following observations were noted;

A black solid formed upon heating the sample, and when the tube was set aside to cool down, condensation the side of the tube was observed.

Ans:

Write the balanced chemical equation and classify the reaction.

Ans:

Sulfur does not dissolve in water, but it does dissolve in carbon disulfide. Potassium nitrate does not dissolve in carbon disulfide, but does in water. Carbon does not dissolve in either water or carbon disulfide. Using the above data, outline a process for separating these three components of gunpowder.

Ans:

Outline the procedure to determine the identity of an unknown liquid using physical properties such as solubility, boiling point and density.

The following list of compounds can be your unknown: isopropyl alcohol, acetone, ethyl alcohol, benzene

Indicate what information about the known liquids must be provided so you can identify your unknown liquid.

Ans:

II. Quantitative Problems

A chemistry student determined the empirical formula for titanium sulfide (Ti_xS_y). To do so, she reacted titanium with excess sulfur in a crucible, and recorded the following data: 10 points

Mass of Crucible 10.020 g

Mass of crucible + titanium 8.820 g

Mass of crucible and product 30.600g

Mass of product:

Mass of S in the product:

Mol Titanium:

Mol S in product:

Ti to S ratio

Empirical formula of titanium sulfide:

A student was given an unknown chloride of copper. He was asked to determine the formula of the chloride. He mixed the chloride with 1.543 g Zn. When the reaction was completed, the copper that was formed from the reaction was transferred (following a series of steps to detach the copper solid from the Zn solid and washing off zinc chloride from it) to a previously weighed out evaporating dish.

Mass of copper(?) chloride = 2.1810 g

Mass of evaporating dish = 10.3201 g

Mass of evaporating dish + copper (after drying) = 11.3440 g

Mass of copper = ____________

Mol of copper in original chloride?

Answer:

Mass of chloride in the original sample?

Answer:

Mol of Cl in the chloride?

Answer

Given the following data: 5 points

Mass of metal= 2.5230 g

Initial Volume of water- 7.32mL

Final Volume after placing metal in the cylinder – 7.75mL

Calculate the density of the metal

Answer:

Empirical Formula of Zinc Chloride

Mass of watch glass (g) = 35.535g

Mass of watch glass + zinc chloride (initial) = 35.737g

Mass of watch glass + zinc chloride (final) = 35.762g

mass change on watch glass = .025g

Mass of zinc chloride in 50 mL beaker = 30.347g

Trial #1

initial buret volume zinc chloride = 49.9 mL

Final buret volume = 26.20 mL

volume zinc chloride titrated = 23.70 mL

concentration of EDTA = .0225 mol/L

initial buret volume EDTA = 49.90 mL

final buret volume EDTA = 26.30 mL

volume EDTA tritrant used = 23.60 mL

Problems:

a. mass zinc chloride titrated

b. # moles EDTA used in titration

c. # moles Zn2+ titrated

d. mass Zn in titrated mass

e. mass Cl in titrated mass

f. # moles Cl in titrated sample

g. molar ratio of Zn:Cl in zinc chloride

h. empirical formula of zinc chloride

Additional Information:

mass of zinc chloride used (solid) = .32g

10 mL of distilled water used to dissolve zinc chloride

volume of zinc chloride solution used = 25 mL

a 100 mL volumetric flask used to pour in liquid

2 mL of pH 10 buffer used

titrated solution until mixture went from purple to blue by adding 2 mL of EDTA solution at a time into flask.

Please detail the calculations for I also have to study the calculation for my midterm.

Thank you!

Compare the pH of the milk sample and the pH at which casein solid forms

What made Gravity?

Writing assignment - Position Paper on the Impact of Technology 

You must support one of the following positions in a 5-7 paragraph essay:

1. The positive impact of technology far outweighs any negative effects.

2. The negative impact of advancements in technology felt by many people outweighs the positive effects enjoyed by few.

Select one or more technological advances, such as cell phones, the internet, stem cell research, etc., on which to focus your essay. Support your arguments with strong reasoning and with specific examples and evidence.

Top Scores (30 - 20) - The top scoring students will do the following:

At least three pros and three cons are mentioned

Demonstrates clear understanding of current issues. Specific problems are discussed and goals for the future are included.

Writing is clear and focused; holds reader's attention
The order and structure moves the reader through the text and the central idea of theme is clear.

The writing has a clear purpose and speaks clearly to the audience. It is compelling and engaging.

The argument is logical. The words are powerful and engaging. The message is conveyed precisely, and naturally.

The writing flows easily. Sentences are well built with a strong and varied structure.
The writing demonstrates a strong grasp of standard writing conventions.

Follow the picture for a better understanding of the assignment.