Practice: What is the mass percent of NH_{3} of a 1.25 m aqueous solution of NH_{3}?

Subjects

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Solutions, Molarity and Intermolecular Forces | 7 mins | 0 completed | Learn |

Henry's Law | 20 mins | 0 completed | Learn Summary |

Calculate Molarity | 27 mins | 0 completed | Learn Summary |

Mass Percent | 10 mins | 0 completed | Learn |

Molality | 15 mins | 0 completed | Learn |

Mole Fraction | 14 mins | 0 completed | Learn |

The Colligative Properties | 45 mins | 0 completed | Learn |

Additional Practice |
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Making Solutions |

Freezing Point Depression |

Colloid |

Additional Guides |
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ppm |

The Freezing Point Depression |

Boiling Point Elevation |

**Molality (m) **represents the amount of solute dissolved per kilogram of solvent.

Example #1:

**Molality** is depicted as moles of solute per kilograms of solvent.

Concept #1: Ionic molality or osmolality represents the molality of dissolved ions in a solution.

Example #2:

A solution is prepared by dissolving 43.0 g potassium chlorate, KClO_{3}, in enough water to make 100.0 mL of solution. If the density of the solution is 1.760 g/mL, what is the molality of KClO_{3} in the solution? MW of KClO_{3} is 122.55 g/mol.

Example #3:

If the molality of glucose, C_{6}H_{12}O_{6}, in an aqueous solution is 2.56 what is the molarity? Density of the solution is 1.530 g/mL.

Example #4:

What is the ionic molality of nitrate ions in 0.305 m lead (IV) nitrate, Pb(NO_{3})_{4}?_{. }

Practice: What is the mass percent of NH_{3} of a 1.25 m aqueous solution of NH_{3}?

Ethylene glycol (C2H6O2) is a common automobile antifreeze, dissolving in water to make a nonelectrolytic solution.
A certain ethylene glycol solution is 40.0% by mass. What is the concentration of the solution in units of molality (m)?

What mass (in g) of NH 3 must be dissolved in 475 g of methanol to make a 0.25 m solution?
A) 2.02 g
B) 4.94 g
C) 1.19 g
D) 8.42 g
E) 1.90 g

A solution of 6.5% per weight H 2SO4 is dissolved in water. What is this concentration in molality? (Molar weight = 98 g/mol)
A. 2.3 m
B. 0.71 m
C. 4 x 10–14 m
D. 0.02 m

How many grams of potassium nitrate (KNO3) do I need to dissolve in 800. g of water to prepare a 0.425 m KNO3 solution?

What is the molality (m) of a 1.25 M aqueous solution of sugar (C 6H12O6, 342.3 g/mol) which has a density of 1.14 g/mL?
a) 0.742 molal
b) 1.25 molal
c) 0.614 molal
d) 0.966 molal
e) 1.76 molal

What is the molality of an ascorbic acid solution made by dissolving 100.0 g of ascorbic acid, C6H8O6 (MW = 176.126 g/mol) in 750.0 g of water ( answers given in molal units)?
a) 1.14
b) 0.032
c) 0.0046
d) 4.3
e) 0.757

What is the molality is an ascorbic acid solution made by dissolving 100.0 g of ascorbic acid, C6H8O6 (MW = 176.126 g/mol) in 750.0g of water (answers given in mole units)?
a. 1.14
b. 0.032
c. 0.0046
d. 4.3
e. 0.757

An aqueous solution is 2.67 M in HNO 3 and has a density of 1.1064 g cm –3. Compute the molality of the HNO3 in this solution in mol/kg.
a. 2.41
b. 2.97
c. 3.72
d. 2.32
e. 2.84

What is the molality of 150.0 g of NH 3 dissolved in a solution that is 1.25 Liters? The density of the solution is 1.45 g/mL.
A. 4.86
B. 5.30
C. 7.04
D. 8.28
E. 12.0

What is the molality of 150.0 g of NH 3 dissolved in a solution that is 1.25 Liters? The density of the solution is 1.45 g/mL.
A. 4.86
B. 5.30
C. 7.04
D. 8.28
E. 12.0

Calculate the molality of a solution formed by dissolving 27.8 g of LiI in 500.0 mL of water.
A) 0.394 m B) 0.556 m C) 0.241 m D) 0.254 m E) 0.415 m

3.52 g NH4Cl (MW = 53.45 g/mol) is added to 12.4 g of water. Calculate the molality of ammonium chloride in the solution.
a) 5. 31 m
b) 0.0872 m
c) 15.2 m
d) 15.2 x 103 m

What mass (in g) of NH 3 must be dissolved in 475 g of methanol to make a 0.250 m solution?
a) 2.02 g
b) 4.94 g
c) 1.19 g
d) 8.42 g
e) 1.90 g

What mass of water is needed to dissolve 292.5 g of NaCl to produce a 0.25 m aqueous solution?
Formula Molar Mass of NaCl is 58.5 g•mol –1.
a) 20 kg
b) 5.0 kg
c) 0.80 kg
d) 0.050 kg

Ethylene glycol (C2H6O2) is a common automobile antifreeze, dissolving in water to make a nonelectrolytic solution.
A certain ethylene glycol solution is 30.0% by mass. What is the concentration of the solution in units of molality (m)?

Fluorocarbons (compounds that contain both carbon and fluorine) were, until recently, used as refrigerants. The compounds listed in the following table are all gases at 25 oC, and their solubilities in water at 25 oC and 1 atm fluorocarbon pressure are given as mass percentages.
Fluorocarbon
Solubility (mass %)
CF4
0.0015
CClF3
0.009
CCl2F2
0.028
CHClF2
0.30
For CHClF2, calculate the molality of a saturated solution.

What is the molality of a solution made by dissolving 38 g of C 10H8 in 425 g of C7H8? a. 0.546 mb. 12.3 mc. 0.998 md. 4.65 me. 0.698 m

What is the molality of a 4.0 M NaOH solution? The density of the solution is 1.04 g/mL. In 1 L solution.
a) 0.15 m
b) 4.5 m
c) 0.18 m
d) 4.0 m
e) 3.8 m

Molality from weight percent: What is the molality of an 18.0% aqueous solution of KCl?

What mass (in g) of NH3 must be dissolved in 475g of methanol to make a 0.250 m solution?

30 grams of liquid ethanol, CH3CH2OH, are mixed with 70 g water. The density of pure ethanol is 0.789 g/mL. The density of water is 1 g/mL. What is the molality of the ethanol in this solution?

A 9.2 M perchloric acid (HClO 4) solution has a density of 1.54 g cm -3 at 25°C. Calculate the molality of the perchloric acid.a) 5.97b) 14.2c) 10.6d) 14.9e) none of the given answers

An aqueous solution is 2.67 M in HNO 3 and has a density of 1.1064 g cm -3 . Compute the molality of the HNO3 in this solution in mol/kg.a) 2.42b) 2.97c) 3.72d) 2.32e) 2.84

An aqueous solution is 2.67 M in HNO3 and has a density of 1.1064 g cm -3. Compute the molality of the HNO3 in this solution in mol/kg.a) 2.76b) 2.97c) 2.84d) 3.72e) 2.32

How many grams of glucose (C6H12O6) must be dissolved in 563 g of ethanol (C2H5OH) to prepare a 2.40 x 10 -2 m solution?A. 2.43 g C6H12O6B. 4.32 g C6H12O6C. 0.000075 g C6H12O6D. 437 g C6H12O6E. 7.69 C6H12O6

Which of the following statements is FALSE?a) The minority component of a mixture is called the soluteb) The majority component of a mixture is called the solventc) A diluted solution contains a relatively small amount of solute relative to solventd) The molarity of a solution is the moles of solute divided by liters of solvente) The molality of a solution is the moles of solute divided by kg of solvent

What is the total ionic molality in an aqueous solution prepared by dissolving 0.200 moles of aluminum perchlorate, Al(ClO4)3 in 900.0 g water?

A solution of ethanol, C2H6O, is prepared by dissolving 14.0 g C2H6O in 100.0 g water. (Molar mass ethanol = 46.07 g/mole) Find the molality of the solution.

Calculate the molality of a 23.0% by mass acetic acid, HC 2H3O2, solution. (molar mass = 60.05 g/mole)

What is the molality of naphthalene (C10H8) when 10.5 g of the compound are dissolved in 325 g of benzene (C6H6)?
A. 0.252 m
B. 0.0819 m
C. 13.4 m
D. 32.3 m

What is the molality of a 10.6
% by mass glucose (C6H12O6) solution? (The density of the solution is 1.04 g/mL).

Ascorbic acid (vitamin C, C6H8O6) is a water-soluble vitamin. A solution containing 81.5 g of ascorbic acid dissolved in 220 g of water has a density of 1.22 g/mL at 55oC.Calculate the molality of ascorbic acid in this solution.

A solution is made containing 21.2 g phenol (C6H5OH) in 450 g ethanol (CH3 CH2OH).Calculate the molality of phenol.

The density of toluene (C7H8) is 0.867 g/mL, and the density of thiophene (C4H4S) is 1.065 g/mL. A solution is made by dissolving 8.60 g of thiophene in 260 mL of toluene.Calculate the molality of thiophene in the solution.

If an aqueous solution is very dilute, will its molality be greater than its molarity, nearly the same as its molarity, or smaller than its molarity?

Calculate the molality of the following: (a) A solution containing 85.4 g of glycine (NH2CH2COOH) dissolved in 1.270 kg of H2O

A solution contains 22.4 g glucose (C6H12O6) dissolved in 0.500 L of water. What is the molality of the solution? (Assume a density of 1.00 g/mL for water.)

Calculate the molality of each of the following solutions:(a) 583 g of H2SO4 in 1.50 kg of water—the acid solution used in an automobile battery

Calculate the molality of each of the following solutions:(b) 0.86 g of NaCl in 1.00 × 102 g of water—a solution of sodium chloride for intravenous injection

An automobile antifreeze mixture is made by mixing equal volumes of ethylene glycol (d = 1.114 g/mL; ℳ = 62.07 g/mol) and water (d = 1.00 g/mL) at 20°C. The density of the mixture is 1.070 g/mL. Express the concentration of ethylene glycol as:(d) Molality

An aqueous solution contains 4.6 % NaCl by mass. Calculate the molality of the solution.

How much dry solute would you take to prepare each of the following solutions from the dry solute and the solvent?126 g of 0.220 m NaNO3

What is the molality of a solution of 18% by mass cadmium sulfate, CdSO4 (molar mass = 208.46 g/mol) by mass?A) 0.53 mB) 0.44 mC) 0.86 mD) 2.10 mE) 1.05 m

What is the molality of a 32.0% by weight aqueous solution of acetone (C 3H6O)?A. 8.10B. 7.80C. 7.12D. 6.56E. 5.74

Calculate the molality of each of the following solutions:(b) 125 g of NH4NO3 in 275 g of water—a mixture used to make an instant ice pack

Brass is a substitutional alloy consisting of a solution of copper and zinc. A particular sample of red brass consisting of 81.0% Cu and 19.0% Zn by mass has a density of 8760 kg/m3 .What is the molality of Zn in the solid solution?

An aqueous solution contains 32% HCl by mass.Calculate the molality of the solution.

How many grams of Na 2SO4 (142.05 g/mol) should be added to 175 mL of water to prepare a 0.555 m solution of Na 2SO4? Assume the density of water is 1.00 g/mL.a. 201 gb. 55.2 gc. 13.8 gd. 91.2 ge. 54.2 g

A solution is made containing 12.6 g of methanol CH 3OH (32.04 g/mol) in 154 g of water. H20 (18.02 g/mol)c) Calculate the molality of methanol:a. 2.55 mb. 0.944 mc. 1.62 m d. 1.79 me. 0.272 m

Calculate the number of moles of solute present in each of the following aqueous solutions.86.4 g of 0.180 m KCl,

The density of acetonitrile (CH3 CN) is 0.786 g/mL, and the density of methanol (CH3 OH) is 0.791 g/mL. A solution is made by dissolving 23.0 mL CH3 OH in 98.7 mL CH3 CN.What is the molality of the solution? Assuming CH3OH is the solute and CH3CN is the solvent.