1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
ivann1987 [24]
2 years ago
8

The normal freezing point of water (H2O) is 0.00 oC and its Kf value is 1.86 oC/m. A nonvolatile, nonelectrolyte that dissolves

in water is antifreeze (ethylene glycol). How many grams of antifreeze, CH2OHCH2OH (62.10 g/mol), must be dissolved in 280.0 grams of water to reduce the freezing point by 0.400 oC
Chemistry
1 answer:
adelina 88 [10]2 years ago
6 0

Answer:

3.74g of ethylene glycol must be added to decrease the freezing point by 0.400°C

Explanation:

One colligative property is the freezing point depression due the addition of a solute. The equation is:

ΔT=Kf*m*i

<em>Where ΔT is change in temperature = 0.400°C</em>

<em>Kf is freezing point constant of the solvent = 1.86°C/m</em>

<em>m is molality of the solution (Moles of solute / kg of solvent)</em>

<em>And i is Van't Hoff constant (1 for a nonelectrolyte)</em>

Replacing:

0.400°C =1.86°C/m*m*1

0.400°C / 1.86°C/m*1 = 0.215m

As mass of solvent is 280.0g = 0.2800kg, the moles of the solute are:

0.2800kg * (0.215moles / 1kg) = 0.0602 moles of solute must be added.

The mass of ethylene glycol must be added is:

0.0602 moles * (62.10g / mol) =

3.74g of ethylene glycol must be added to decrease the freezing point by 0.400°C

<em />

You might be interested in
Omg pls help i dunno what the frick frack this is
snow_lady [41]

Answer:

1. Mass of KCl produced = 774.8 g of KCl

2. Mass of KNO₃ produced = 13.837g

3. Moles of NaOH made = 0.846 moles

4. Moles of LiCl produced = 0.846 moles

5. Moles of CO₂ produced = 207.6 moles

Explanation:

1. From the equation of reaction, 1 mole of ZnCl₂ produces, 2 moles of KCl.

5.02 moles of ZnCl₂ will produce, 2 × 5.02 moles of KCl = 10.4 moles of KCl

Molar mass of KCl = (39 + 35.5) g/mol = 74.5 g/mol

10.4 moles of KCl = 10.4 × 74.5 g

Mass of KCl produced = 774.8 g of KCl

2. Mole ratio of KNO₃ and KOH = 1:1

O.137 moles of KOH will produce 0.137 moles of KNO₃

Molar mass of KNO₃ = 101 g/mol

Mass of KNO₃ produced = 0.137 × 101 g = 13.837g

3. Molar mas of Ca(OH)₂ = 74.0 g

Moles of Ca(OH)₂ in 31.3 g = 31.3/74.0 = 0.423 moles of Ca(OH)₂

Mole ratio of NaOH and Ca(OH)₂ in the reaction = 2 : 1

Moles of NaOH made = 2 × 0.423 = 0.846 moles

4. Molar mass of MgCl₂ = 95.0 g

Moles of MgCl₂ in 40.2 g = 40.2/95.0 = 0.423 moles

From the reaction equation, mole ratio of MgCl₂ and LiCl = 1:2

Moles of LiCl produced = 2 × 0.423 = 0.846 moles

5. From the equation of reaction, 1 mole of C₆H₁₀O₅ produces 6 moles of cO₂

34.6 moles of C₆H₁₀O₅ will produce 34.6 × 6 moles of CO₂

Moles of CO₂ produced = 207.6 moles

4 0
2 years ago
What is the total amount of heat released when 94.0 g water at 80.0 °C cools to form ice at −30.0 °C?
Wewaii [24]

Answer:

The total amount of heat released  is  68.7 kJ

Explanation:

Given that:

mass of water = 94.0 g

moles of water = 94 / 18.02 = 5.216

80⁰C   ------>  0⁰C  -------->    -30⁰C

Q1 = m Cp dT

      = 94 x 4.184 x (0 - 80)

     = -31463.68 J

     = -31.43 kJ

Q2 = 6.01 x 10^3 x 5.216

    = - 31348.16 J

   = -31.35 kJ

Q3 = - 94 x 2.09 x 30

    = - 5893.8 J

   = -5.894 kJ

Total heat = Q1 + Q2 + Q3  = -31.43 kJ  + (-31.35 kJ  ) + (-5.894 kJ )  = -68.7 kJ

Total heat released = -68.7 kJ

Note that the "negative sign" simply indicates heat released, therefore no need to put it in the answer.

6 0
3 years ago
How many moles of I(iodine)2 are there in a 500.0g bottle? Please include significant figures
dolphi86 [110]

Answer:

Number of moles = 1.97 mol

Explanation:

Given data;

Number of moles of I₂ = ?

Mass = 500.0 g

Solution:

Number of moles = mass/ molar mass

Molar mass of  I₂ = 253.8 g/mol

Number of moles = 500 g / 253.8 g/mol

Number of moles = 1.97 mol

4 0
3 years ago
The center of the earth is very hot
Arturiano [62]

true. is this what you were looking for?

8 0
3 years ago
What's the ionic compound formula for zinc bicarbonate
raketka [301]
Zn(HCO3)2 is the compound for Zinc Bicarbonate
6 0
3 years ago
Read 2 more answers
Other questions:
  • Typically, water runs through the baseboard copper tubing and, therefore, fresh hot water is constantly running through the pipi
    13·1 answer
  • A certain compound is made up of one carbon (c) atom, two bromine (br) atoms, and one oxygen (o) atom. what is the chemical form
    10·2 answers
  • In the same class two students find that a piece of wood with a mass of 70g has a volume of 103 cm3 they conclude the wood is oa
    6·1 answer
  • Which statement best describes the compressibility of a gas? A Increasing the temperature of a gas decreases the pressure. B Inc
    14·2 answers
  • True or false <br> On the Celsius temperature scale there are not negative numbers
    11·2 answers
  • water is conductor or insluator? nails are conductor or insulator? key chains are conductor or insulator?
    6·1 answer
  • BRAINLIEST ASAP! PLEASE HELP ME :)<br><br> What ancient Greek theory did Robert Boyle help dispel?
    15·1 answer
  • A chemical reaction occurs between Calcium, Oxygen, and Chlorine. The reaction is demonstrated:
    15·2 answers
  • Explain the difference between plate tectonics and tectonic plates.
    12·2 answers
  • How can the Swartz process be modified to work for bacteria? Explain.​
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!