Trabajo Practico 2º trimestre, Araceli Martinez y Franco Soto

TRABAJO PRACTICO

5º1 - EET Nº1 - ELECTRONICS

Questions of Think Section:

1.  Scientists in the 1700's were aware of electricity, but they were not sure _____.
2. Oxidation and reduction are processes through which _____.
3. Rechargeable batteries are different than standard batteries because _____.
4. Rechargeable batteries can no longer function when _____.
5. Batteries enable us to _____.

6. The tissue of living organisms does not contain solid metal, like a copper wire or a zinc plate. However, electric current flows through nerves and muscles. How does current flow through living tissue? (Hint: think about the paper and cloth layers in Volta’s pile)

7. Why do rechargeable batteries eventually lose their ability to be recharged?

Answer:

1. If electricity would flow through metal. (C)
2. Substances lose and gain electrons. (B)
3. Their oxidation-reduction reactions are reversible. (A)
4. Changes to their surfaces prevent electrons from flowing. (D)
5. Store electric charge in a portable way. (A)
6. Living tissue acts as the cloth layer in the  volta stack , and because the tissues are composed of a high percentage of water, that turns out to be a great electric conductor, allow the conduction of electric current.
7. Because over time the repetition of loading and unloading, causes imperfections and irregularities in the metal surface that causes an incorrect oxidation, not so allowing electrons to flow in an electrical circuit and therefore the battery will no longer served

Questions Extra:

• Complete the text. Use: daily / power / phones / batteries / science / slowly/ finally

Batteries are a triumph of -1- science because they allow smart -2- phones and other technologies to exist without making us to a infernal tangle of -3- daily cables. Yet even the best  -4- batteries will diminish -5- finally , -6- slowly  losing capacity until they -7- power die.

• Answer

1. Where were Luigi Galvani and Alessandro Volta from? - Both were Italian scientists
2. When did they become important scientists? -They become important scientists when they discover the electric current, but Volta was the one who discovered why that the electric flows current.
3. Which animal did they use for their experiments? - They used a frog for his experiments

• Complete these ideas with verbs in the Passive Voice. Why do you need PRESENT tense only?

e.g. In this experiment copper and zinc are stacked with pieces of paper. (stack)

1. The reactions in a battery were called “oxidation” and “reduction”. (call)
2. Electrons will lost in a process called “oxidation” (lose)
3. These electrons were regained by the water. (regain)
4. Hydrogen gas was produced in the “reduction” process. (produce)
5. The standard unit of electric potential was called “volt” (call)
6. A flow of electrons between two metals were produced by the combination of “oxidation” and “reduction” processes. (produce)

• Are these sentences TRUE or FALSE?

1. In modern batteries, scientists replaced the chemical solution with dry cells filled with chemical paste. TRUE
2. The principle is completely different (from old batteries). FALSE
3. A metal oxidizes sending electrons to do some work before they are regained by a substance being reduced.TRUE
4. The battery dies when it has oxidised. TRUE
5. Electricity provides more electrons for the metal to be oxidised. FALSE

• Put these events in chronological order. Complete who did what.

(according to the video). Copy the final narrative text.

Who?		What did he/they do in the experiment?
Luigi Galvani Alessandro Volta Both	a-	called the violent movement of the leg: “animal electricity”.
	b-	made an experiment with zinc and copper separated by paper soaked in a salt water solution.
	c-	used a metal instrument to touch the frog’s leg making the leg muscles jump.
	d-	were Italian scientists in the 18 Century.
	e-	created the first battery.
	f-	thought that there wasn’t an “animal electricity” but a reaction to the metallic tool..
	g-	made an experiment with frogs.
	h-	thought that this electricity was the essence of life.

1º d- Both were Italian scientists in the 18 Century.

2º g- Luigi Galvani made an experiment with frogs.

3º c- Luigi Galvani used a metal instrument to touch the frog’s leg making the leg muscles jump.

4º a- Luigi Galvani called the violent movement of the leg: “animal electricity”.

5º h- Luigi Galvani thought that this electricity was the essence of life.

6º f- Alessandro Volta thought that there wasn’t an “animal electricity” but a reaction to the metallic tool..

7º b- Alessandro Volta made an experiment with zinc and copper separated by paper soaked in a salt water solution.

8º e- Alessandro Volta created the first battery.

Both were Italian scientists in the 18 Century. Luigi Galvani made an experiment with frogs. He is used a metal instrument to touch the frog’s leg making the leg muscles jump.

Luigi Galvani called the violent movement of the leg: “animal electricity” and thought that this electricity was the essence of life.

Alessandro Volta thought that there wasn’t an “animal electricity” but a reaction to the metallic tool. He made an experiment with zinc and copper separated by paper soaked in a salt water solution and it was created the first battery.

• Make a list of  6 (six) NEW or OLD technical vocabulary items (learned or revised in this video)

	OLD VOCABULARY	NEW VOCABULARY	time
e.g.	electrons	--	1:42
1-	Animal electricity	Impulso electrico	1:06
2-	Battery	--	1:40
3-	Scientist	--	0:48
4-	Chemical solution	Chemical paste	1:32
5-	--	Oxidation and Reduction	1:34
6-	--	Volts	2:04