Explanation

(a) Definition of Electrochemical Cell: Electrochemical cell is defined as a device/cell which converts chemical energy to electrical energy/or electricity is generated by a chemical change.

(b) Aluminium can be prepared commercially by the application of electrolysis:

(i) Name the: I. Electrolyte used in the process: (i) Aluminium oxide/(Molten) alumina. II. Bauxite. III. Carbon electrodes/graphite electrodes.

(ii) Reasons why cryolite, NaAl F\(_6\) is added to the electrolyte: –As a solvent. –Helps reduce the melting point of alumina (Al\(_2\)O\(_3\)). –To increase the conductivity of electrolyte.

(c)(i) Gaseous fuels produced from coke: –Producer gas. –Water gas.

(c)(ii) Water gas.

(iii) Reason for your answer in(c)(ii): The producer gas contains about 67%/More non-combustible nitrogen and 33% less combustible carbon (II) oxide while water gas contains equal amount of combustible carbon (II) oxide and hydrogen.

(iv) Balance equation for each production of gaseous fuel: Producer gas. 2C\(_{(s)}\) + O2\(_{2(g)}\) + 4N\(_{2(g)}\) --> 2CO\(_{(g)}\) +4N\(_{2(g)}\). Water gas: C\(_{(s)}\) + H\(_{2}\)O —> CO\(_{(g)}\) + H\(_{2(g)}\)

(d)(i) What would be observed when:

I. Chlorine gas is bubbled through aqueous sodium iodide. –Colourless solution turn reddish brown.

II. Chlorine gas is passed over heated iron in a hard glass tube. –Grey silvery solid turns brown.

III. Aqueous silver trioxonitrate (V) is added to aqueous sodium bromide. –Cream/(pale) yellow precipitate.

(ii) Chemical equation for reactions in (d)(i):

(i) Cl\(_2\) +2Nal ---> 2NaCl + l\(_2\)

(ii) 2Fe +3Cl\(_{2}\) —> 2FeCl\(_{2}\)

(iii) AgNO\(_{3}\) +NaBr —> NaNO\(_3\) + AgBr.

Explanation

AT LAST, WE ARRIVED SAFELY

Life is full of unexpected surprises. There are many opportunities when one can secretly wish for something exiting to happen. Something out of the ordinary. The real surprise is when the wish unexpectedly comes true. I never believed that something like this could ever happen to me. Such a thing that would make me stop and look back at the events in awe. I think you would agree that something as simple as being lost in the forest for less than ten minutes should have no influence on my life If you do agree, that makes both of us wrong.

Throughout my childhood, I loved the wildlife. My family and I would always go for a walk in the downtown forest of Conte's paradise. There are many times I thought of what could happen if we were to lose our way from the trail and have to live off of the land until we found our way back to civilization. I thought it would be the greatest experience ever.

As my brothers and I grew older, we continued to go for these walks with our parent but the experience of living In the forest I soon forgot. That's when it happened. We decided to take a different path off the main trail. Before I knew it, the path had disappeared and no one in my family could tell where we had come from It was so unexpected. it gave me a feeling of excitement that cant be described Everything in the forest seemed different. The trees were a deeper shade of green leaves. The birds chirped in a different tone. Vines covered almost every inch of the ground. One part of me never wanted this moment to end. I felt completely free from the stress of my outside of the woods. It was this moment that I realized that I would much rather stay here for the rest of my life than go back to the society.

I think that another reason that I felt carefree was because my parents didn't panic.

Uzodinma Confidence

Correct Answer: C. lending money to borrowers

Explanation

Lending money to borrowers is one profitable business undertaken by the commercial banks. These banks lend money to borrowers and charge interest for the amount lend for the duration of the loan. The interest paid by borrowers is the lender's (bank) is the profit.

Correct Answer: C. appointed seven deacons to undertake the care of the new Christians

Correct Answer: D)

C₂₄H₄₈

Correct Answer: D. for research and publicity

Correct Answer: D. fiscal policy

Explanation

a.Classification of living things is the grouping/arrangement of organisms; with similar characteristics based on structural/genetic/cellular/evolutionary trends; for easy identification.

bi. -cause various plant/animal diseases;

-act as decomposers;

-recycle nutrients;

-bring about fermentation in breweries;

-used in baking industries;

-serve as source of food;

-are used in pharmaceutical industries/production of antibiotics/vitamins;

-destroy various substances/cloth/paper/wood/food

bii. -are involved in nutrient recycling;

-purify the environment/reduce greenhouse effects;

-provide shade/shelter;

-provide food;

-provide oxygen;

-prevent erosion;

-are sources of timber for building/construction;

-provide materials for pharmaceuticals/production of drugs.

c.

Correct Answer: A. A 300Ω resistor is connected to it in parallel

Correct Answer: D. fulfil all righteousness