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Please help me with my midterm! Show solution if possible for better understandi

ID: 955563 • Letter: P

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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 (TixSy). 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:

Explanation / Answer

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

Answer: Cation First then anion.

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.

Answer: 3 CaCl2 + 2 Na3PO4 -----> 6 NaCl + 1 Ca3(PO4)2

What is the type of the chemical reaction?

Answer: Its a precipitation reaction. (Double Displacement)

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.

Answer:

It still will be copper (II) sulfate, but it will be an aquation of it due to the mixture of water.

CuSO4 + 5H2O --> CuSO4.5H2O

Type of reaction: Synthesis.

5 questions answered.