Ellingham Diagram

Q. With respect to an ore, Ellingham diagram helps to predict the feasibility of its:

1. Electrolysis
2. Thermal reduction
3. Vapour phase refining
4. Zone refining

Q. A metal oxide has the formula M2O it can be thermally decomposed to the metal and oxygen 5.8 g of the metal oxide forms 400mh of oxygen gas on complete decomposition .the atomic weight of the metal is(1)56;(2)23;(3)27;(4)108

Q. With respect to an ore, Ellingham diagram helps to predict the feasibility of its:

1. Electrolysis
2. Thermal reduction
3. Vapour phase refining
4. Zone refining

Q. Reaction(s) involved in thermite process can be

1. $3M{n}_3{O}_4+8Al\to 9Mn+4A{l}_2{O}_3$
2. $C{r}_2{O}_3+2Al\to A{l}_2{O}_3+2Cr$
3. $2Fe+A{l}_2{O}_3\to 2Al+F{e}_2{O}_3$
4. $3Ti{O}_2\left(s\right)$ $+4Al\left(s\right)$ $\to$ $2A{l}_2{O}_3$ $\left(s\right)$ $+3Ti\left(l\right)$

Q.

In the Ellingham diagram for oxides, the general trend for the graphs for metal to metal oxide is

1. They slope upwards

2. They are all parallel to the $\Delta G^{\circ }$ = 0 horizontal axis

3. There is no common trend

4. They slope downwards like the $2C+O_2$ $\to$ 2CO line

Q.

For the following question, the answer is an integer between 0 and 9 (both inclusive).

In the Ellingham diagram for oxides, there are x lines for the reaction(s) between C and O. What is x?

___

Q. 34.Zno----zn2+ o2 + e This come under metal excess defect. Does metal excess defect occurs only in oxides of metal. Also what type of compounds show this defect.

Q.

The $\frac{{\Delta }_f{G}^{\circ }}{T}$ line for $C+O_2$ $\to$ $C{O}_2$ is nearly parallel to the ${\Delta }_f{G}^{\circ }$ = 0 – True or False?

1. True

2. False

Q.

You are given an Ellingham diagram (deliberately not shown). It is given that for almost all practically achievable temperatures, the $Fe\to F{e}_2{O}_3$ line lies above the $Al\to A{l}_2{O}_3$ line and ${\Delta }_f{G}^{\circ }$ for both $A{l}_2{O}_3$ and $F{e}_2{O}_3$ are negative. Which of the following statements is/are true?

1. Under the given conditions, neither metal can reduce the other oxide

2. Fe can reduce $A{l}_2{O}_3$ into Al

3. Al can reduce $F{e}_2{O}_3$ into Fe

4. Both b and c

Q. a meatl forms two oxides. the higher oxide contains 80% metal.0.72g of the lower oxide gave 0.8g of higher oxide when oxidised.then the ratio of the weight of oxygen that combines with the fixed weight of the metal in the two oxides will be

Q. A metal forms two oxides. The higher oxidecontains 80% metal. 0.72 g of the lower oxide gave0.8 g of higher oxide when oxidised. Then the atioof the weight of oxygen that combines with the fixed weight of the metal in the two oxides will b

Q. Select the incorrect statement:

1. In the decomposition of a metal oxide into oxygen and solid metal, entropy increases
2. Decomposition of an oxide is an endothermic change
3. 
   $\Delta G°vsT$ graph for the formation of $C{O}_2$ has negative slope
4. $\Delta G°vsT$ graph for the formation of $CO$ has negative slope.

Q.

You are given an Ellingham diagram (deliberately not shown). It is given that for almost all practically achievable temperatures, the $Fe\to F{e}_2{O}_3$ line lies above the $Al\to A{l}_2{O}_3$ line and ${\Delta }_f{G}^{\circ }$ for both $A{l}_2{O}_3$ and $F{e}_2{O}_3$ are negative. Which of the following statements is/are true?

1. Under the given conditions, neither metal can reduce the other oxide

2. Fe can reduce $A{l}_2{O}_3$ into Al

3. Al can reduce $F{e}_2{O}_3$ into Fe

4. Both b and c

Q. Ellingham diagrams are a plot of $\Delta G^{\circ }$ vs T for the formation of:

1. oxides
2. halides
3. sulphides
4. all of these

Q. The oxide which cannot act as reducing agent: (1)CO_2 (2)ClO_2 (3)NO_2 (4)SO_{2.