Chem 150 Exam 2

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100

Guess the gibberish

Daze duh rein poe

Taste the rainbow

200

Guess the gibberish

mig heem house

Mickey Mouse

300

sow warp hatch kits

sour patch kids

400

tech a gel pal

take a chill pill

500

birch who'll ray yell lid he

virtual reality

Nomenclature

100

Name me: 

Si₂O₃

B₃N

GeI₄

N₃F₉ 

disilicon trioxide

triboron mononitride

germanium tetraiodide

trinitrogen nonafluoride  

200

Name me:

H₂S

HClO 

CH₃COOH

HF

Hydrosulfuric Acid

Hypochlorous Acid

Acetic Acid

Hydrofluoric Acid

300

write the chemical formula for:

Potassium Superoxide

 Copper(I) Sulfide 

Tin(IV) Oxide 

Chromium(III) Nitride

 KO₂

 Cu₂S 

SnO₂ 

Cr₂N₃

400

write the chemical formula for:

A. Potassium Nitride 

B. Magnesium Sulfite 

C. Phosphorous Acid 

D. Aluminum sulfide

A. K₃N

B. MgSO₃ 

C. H₃PO₃ 

D. Al₂S₃

Molarity

100

what volume, in L, of 12.0M NaOH is needed to make 4.00L of 4M NaOH by dilution with water?

You would need 1.33 liters of 12.0M NaOH

200

calculate the mass of LiCl required to make 50mL of 0.750M LiCl aqueous solution? (mm=42.39g/mol)

1.59 grams of LiCl.

300

A 100 mL sample of sulfuric acid is titrated with 0.250M sodium hydroxide. The titration requires 40.0 mL of the sodium hydroxide solution to reach the endpoint. What is the concentration of the sulfuric acid in the sample?

H₂SO₄(aq)+2NaOH(aq)→Na₂SO₄(aq)+2H₂O(l)

 0.050 M

400

Consider a solution made by dissolving 5.00g of copper(II) sulfate pentahydrate (mm = 249.68g/mol) in enough water to make a 250mL solution. what is the concentration of copper2 ions

The concentration of copper(II) ions (Cu²⁺) is 

0.0800 M.

chemical equations

100

write the molecular and net ionic chemical equations: include states! If no rxn occurs state no reaction. 

 sulfuric Acid_(aq) and barium Hydroxide_(aq)

H₂SO_4(aq)+Ba(OH)_2(aq)→BaSO_4(s)+2H₂O_(l)

2H⁺ + SO4²⁻_(aq) Ba²⁺_(aq) + OH^- → BaSO₄(s) + 2H₂O_(l)

200

write a molecular and net ionic equation. If no rxn occurs state no reaction. 

A solution of KNO₃ is mixed with LiCl

no reaction 

300

Na₂SO₄(aq)+CaCl₂(aq)→CaSO₄(s)+2NaCl(aq)

A 30 mL sample of 1.5 M sodium sulfate solution is mixed with 25 mL of a 1.0 M calcium chloride solution. The resulting reaction produces a precipitate of calcium sulfate. After the reaction, the solid calcium sulfate is collected, dried, and found to have a mass of 3.00 g. Determine the limiting reagent, theoretical yield, percent yield.

(mm of CaSO₄ =136.14g/mol)

Limiting Reagent: CaCl₂ 

Theoretical Yield:3.40g 

Percent Yield: 88.24%

 

400

Write a balanced equation for the following: 

Aqueous hydrochloric acid reacts with solid manganese (IV) oxide to form aqueous manganese (II) chloride, liquid water and chlorine gas

4HCl_(aq)+MnO_2(s)→MnCl_2(aq)+2H₂O_(l)+Cl_2(g)

500

A compound contains only C, H, and O. Combustion of 10.68mg of the compound yields 16.01mg CO₂ and 4.37mg of H₂O. The molecular weight for the compound is 76.1 g/mol. What is the molecular formula?

Empirical C₃H₄O₃

molecular C₆H₈O₆

Surprise me

100

write a balanced equation for the combustion of C₆H₁₂O₆

C₆H₁₂O₆+6O₂→6CO₂+6H₂O

200

Which of the following statements about electrolytes is TRUE?

A) Weak electrolytes completely dissociate into ions in solution.
B) Strong electrolytes only partially dissociate into ions in solution.
C) All ionic compounds are strong electrolytes when dissolved in water.
D) Weak electrolytes produce fewer ions in solution compared to strong electrolytes.

D) Weak electrolytes produce fewer ions in solution compared to strong electrolytes.

300

The combustion of ethanol can be represented by the following balanced chemical equation

C₂H₅OH_(l)+3O_2(g)→2CO_2(g)+3H₂O_(g)

A.  If 46 g of ethanol is combusted, what is the mass of carbon dioxide produced? (Ethanol: 46.08 g/mol, CO₂: 44.01 g)

B. How many moles of water are produced when 92g of oxygen is consumed in the reaction?               (O₂: 32.00g/mol)

C. How many moles of ethanol are required to produce 4 moles of carbon dioxide? 

A. 87.91g CO₂ 

B. 2.875moles H₂O

C. 2 moles C₂H₅OH 

400

find the percent by mass of HCl in a 12M solution that has a density of 1.10g/mL

Percent by mass of HCl=(437.52g/1100g) ×100     ≈ 39.77%

500

Which of the following is not a strong acid?

HCl

HF

HNO₃

HClO

H₂SO₄

HF & HClO

more random ?s

100

Which of the following reactions is a double displacement reaction?

A. 2 H₂+O₂→2H₂O₂ 

B. NaOH+ HCl→ NaCl+ H₂O

C. CH₄+2 O₂→CO₂+2H₂O

D. 2KClO₃→2KCl+3O₂

B. NaOH+ HCl→ NaCl+ H₂O

200

Consider a solution made by dissolving 5.00 g of iron(III) bromide dihydrate in enough water to make a 250. mL solution.  What is the concentration of the iron(III) bromide dihydrate? what is the concentration of chloride ions in this solution? 

FeBr₃⋅2H₂O

Concentration of FeBr3⋅2H2O=(0.0151mol 0.250L) =0.0604M

Concentration of Br−= (3×0.0604M) =0.181M

300

Urea, CH₄N₂O, is a common fertilizer that is synthesized by the reaction of ammonia (NH₃) with carbon dioxide: 

 2NH_3(aq) + CO_2(g) + CH₄N₂O_(aq) + H₂O_(l) 

 In an industrial synthesis of urea, a chemist combines 136.4 kg of ammonia with 211.4 kg of carbon dioxide and obtains 168.4 kg of urea. Determine the maximum amount of urea that can be produced.  What is the percent yield? How much of the excess reactant will be left over? 

theo yield: 240.7kg of Urea

The percent yield is 69.96%.

The amount of excess carbon dioxide (CO₂) left over is 35.2 kg.