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
ElenaW [278]
2 years ago
14

A useful single-displacement reaction involves thermite, which is a

Chemistry
1 answer:
Licemer1 [7]2 years ago
7 0
The reaction of iron (III) oxide and aluminum is initiated by heat released from a small amount "starter mixture". This reaction is an oxidation-reduction reaction, a single replacement reaction, producing great quantities of heat (flame and sparks) and a stream of molten iron and aluminum oxide which pours out of a hole in the bottom of the pot into sand.

The balanced chemical equation for this reaction is:

2 Al(s) + Fe2O3(s) --> 2Fe(s) + Al2O3(s) + 850 kJ/mol

Curriculum Notes
This chemical reaction can be used to demonstrate an exothermic reaction, a single replacement or oxidation-reduction reaction, and the connection between ∆H calculated for this reaction using heats of formation and Hess' Law and calculating ∆H for this reaction using qrxn = mc∆T and the moles of limiting reactant. This reaction also illustrates the role of activation energy in a chemical reaction. The thermite mixture must be raised to a high temperature before it will react.

To determine how much thermal energy is released in this reaction, heats of formation values and Hess' Law can be used.

By definition, the deltaHfo of an element in its standard state is zero.

2 Al(s) + Fe2O3(s) --> 2Fe (s) + Al2O3 (s)

The deltaH for this reaction is the sum of the deltaHfo's of the products - the sum of the deltaHfo's of the reactants (multiplying each by their stoichiometric coefficient in the balanced reaction equation), i.e.:

deltaHorxn = (1 mol)(deltaHfoAl2O3) + (2 mol)(deltaHfoFe) - (1 mol)(deltaHfoFe2O3) - (2 mol)(deltaHfoAl)

deltaHorxn = (1 mol)(-1,669.8 kJ/mol) + (2 mol)(0) - (1 mol)(-822.2 kJ/mol) - (2mol)(0 kJ/mol)

deltaHorxn = -847.6 kJ

The melting point of iron is 1530°C (or 2790°F).
MARK ME BRAINLIEST

You might be interested in
The amount of a chemical solution is measured to be 2 liters.
irinina [24]
2 liters may be 1.5 to 1.9 rounded up to 2 or 2.1 or 2.4 rounded down to 2.

2 - 1.5 = 0.5

percent error = (absolute error / quantity) * 100

percent error = 0.5/2 * 100% = 0.25 * 100% = 25%

Choice C. 25%.
3 0
3 years ago
If an isotope decays by the process of beta emission, ___.
Kaylis [27]
1. Decreases by 4. (B)
2. The atomic number changes. (B)
3. 56/26 Fe. (C)
4. Potassium-40;t1/2=25 days. (B)
5. Takes place in the upper atmosphere. (A)
3 0
3 years ago
Read 2 more answers
Perform the following mathematical operation, and report the answer to the correct number of significant figures. 0.34 x 0.568=?
slavikrds [6]

The correct answer to the problem is 0.193 which is three significant figures.

<h3>What are significant figures?</h3>

The term significant figures has to do with the figures that have a mathematical meaning. We know that the result has to correspond to the highest number of significant figures.

Hence, If we multiply 0.34 x 0.568 the result ought to be recorded as 0.193 which is three significant figures.

Learn more about significant figures:brainly.com/question/14804345

#SPJ1

6 0
1 year ago
During a chemical reaction, the______
WINSTONCH [101]

Answer:

limiting reagent :)

Explanation:

5 0
2 years ago
Read 2 more answers
What kind of a bond is oc2
nexus9112 [7]

Answer:

A carbon–oxygen bond is a polar convalescent bond between carbon and oxygen. Oxygen has 6 valence electrons and prefers to either share two electrons in bonding with carbon, leaving the 4 nonbinding electrons in 2 lone pairs :O: or to share two pairs of electrons to form the carbon functional group.

8 0
3 years ago
Other questions:
  • What metallic element is sometimes used in flares because it burns bright?
    5·2 answers
  • Which of the following is an example of a decomposition reaction? 1) H2 + O2 ----------→ H2O 2) MgO2 -------------→ Mg + O2 3) M
    15·1 answer
  • (REALLY NEED HELP 30 POINTS )If the mass of a material is 12 grams and the volume of the material is 49 cm^3, what would the den
    12·2 answers
  • 6. Which of the following statements is not true for an astronomical unit?
    5·2 answers
  • A student titrates an unknown amount of potassium hydrogen phthalate (KHC8H4O4, abbreviated as KHP) with 21.30 mL of a 0.1161 M
    7·1 answer
  • Can carbon atoms share electron with four hydrogen atoms to form a methane molecule? Explain.
    11·1 answer
  • Asappp plzz help mee
    12·1 answer
  • A gaseous mixture containing 7.00 moles of nitrogen, 2.50 moles of oxygen, and 0.500 mole of helium exerts a total pressure of 0
    13·1 answer
  • How many grams of KNO3 would recrystallize from 100 g of water, if a saturated solution were cooled from 50 degrees celcius to 2
    10·1 answer
  • Find the mass in grams of 3.21×10^23 molecules of nitrogen gas
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!