Question

8

In the thermite reaction:

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

So much heat is generated that the iron initially formed is a molten liquid. Which of the following statements is consistant with the reaction?

the reaction is endothermic; aluminum is oxidized and iron is reduced.the reaction is not an oxidation reduction reaction.     the reaction is exothermic; aluminum is oxidized and iron is reduced.the reaction is endothermic; aluminum is reduced and iron is oxidized.the reaction is exothermic; aluminum is reduced and iron is oxidized.

9.

The propellent used to help launch the space shuttle in the solid-fuel boosters attached to the vehicle is 1.1 million pounds of ammonium perchlorate and powdered aluminum. The reaction generating the energy to blast the orbitor into space is:

3 NH₄ClO₄(s) + 3 Al(s) ---> Al₂O₃(s) + AlCl₃(s) + 3 NO(g) + 6 H₂O(g)

The energy generated results from oxidation-reduction chemistry.

Write the symbol for the metallic element that is oxidized in the reaction.



Write the symbol for the element that is reduced in the reaction.



What is the name of the first aluminum containing compound listed as a product of the reaction?



What is the name of the other aluminum containing compound listed as a product of the reaction?

10.

A 0.205 g sample of a monoprotic acid was dissolved in 25 mL of water. The acid solution was titrated to its endpoint with 28.1 mL of 0.0788 M NaOH solution. What is the molar mass of the acid?

g/mol

11.

The chemical substances in the first column of the table are either already shown as cations (because they are either polyatomic ions or variably valent elements), or they are known to form cations during the making of an ionic compound. The chemical substances in the first row of the table are either already shown as anions (because they are polyatomic ions), or they are known to form anions during the making of an ionic compound. When no charge is shown, you'll have to figure out what charge an atom of the element is expected to carry as an ion. Complete the table by writing the chemical formula of the compound resulting from combining the ions at the intersecting rows and columns. Remember chemical formulas of ionic compounds do not show charges!!!

	HSO3-	P
Mn3+
Ca
Mn2+

Answer 1

8.

2 Al (s) + F2O3 (s) ---------> Al2O3 (s) + 2 Fe (s)

It is given the question that, during this reaction so much heat is released.

Hence, it is an exothermic reaction.

Note: The reaction which releases energy is called exothermic reaction and the reaction which absorbs energy is called endothermic reaction.

Oxidation: The process of loss of electrons is called oxidation.

Reduction: The process of gain of electrons is called reduction.

In the given reaction,

Al is changed to Al2O3.

Here, The oxidation state of Al changes from 0 (zero) to +3, and hence Al undergoes oxidation.

Note: Increase in oxidation state indicates loss of electrons and hence is oxidation.

And

Fe2O3 is changed to Fe

Here, the oxidation state of Fe changes from +3 to 0 (zero) and hence Fe undergoes reduction.

Note: Decrease in oxidation state indicates gain of electrons and hence is reduction.

Therefore, the give reaction is Exothermic and Al is oxidised and Fe is reduced.