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
Answer:
statement about property is not true
Explanation:
if you think the answer is Grace Mark me as brain a list
science of love
,EXPLANATION:
The initial happy feelings of being in love is stimulated by 3 chemicals in the brain: noradrenaline that stimulates adrenaline production causing that racing heart and sweaty palms; dopamine, the feel-good chemical; and phenylethylamine that is released when we're near our crush, giving us butterflies in our tummies.
- <em>hope</em><em> </em><em>this</em><em> </em><em>will</em><em> </em><em>help</em><em> </em><em>u</em><em>.</em><em>.</em><em>and</em><em> </em><em>plz</em><em> </em><em>mark</em><em> </em><em>this</em><em> </em><em>as</em><em> </em><em>brainliest</em>
I'm assuming that you meant 55 g/cm^
3. Density=
. This is the definition of density. If you rearrange this equation by multiplying each side of the equation by the volume, you get: (Density)(Volume)=Mass. Divide each side by the density to get: Volume=Mass/Density. Now just plug everything in:
V=220 (grams)/55 (grams/cm^3)=<u>4 cm^3</u>
Answer:
Period
Explanation:
Periodic trend along period:
As we move from left to right across the periodic table the number of valance electrons in an atom increase. The atomic size tend to decrease in same period of periodic table because the electrons are added with in the same shell. When the electron are added, at the same time protons are also added in the nucleus. The positive charge is going to increase and this charge is greater in effect than the charge of electrons. This effect lead to the greater nuclear attraction.
The electrons are pull towards the nucleus and valance shell get closer to the nucleus. As a result of this greater nuclear attraction atomic radius decreases and ionization energy increases because it is very difficult to remove the electron from atom and more energy is required.The electron affinity also increases along period because of greater positive charge.
