Lesson 7 Theme: «Indium»Grammar: The future simple tense. Listening: Unbreak my heart

Ex. 6. Translate the sentences into English.

1. 
   Indy is found in very small quantities in nature. 2. The properties of indium belong to the elements of group III. 3. Indium burns in air and forms In2O3 oxide. 4. Many compounds of indium are soluble in water. 5. Diluted hydrochloric acid reacts with indium to form hydrogen. 6. Acetic acid does not dissolve indium. 7. Spectral analysis shows indium blue lines.
   

Ex. 8. Answer the following questions:

1 . What is the occurrence of indium in nature? 2. What properties does indium exhibit? 3. What can you say about commercial applications of indium? 4. What kind of oxide does indium form? 5. What compounds of indium and the galogens are known? 6. In what way does indium react with sulphuric acid? 7. What does the spectral analysis show?

1. Indium was regarded as a laboratory curiosity for many years and.

2. Agar u galogenlar yoki oltingugurt ishtirokida qizdirilsa, to'g'ridan-to'g'ri birikma hosil bo'ladi. Indiy eng yuqori oksidlanish darajasiga o'tadi.

3. It would hardly be possible to think of its application, for the available supply at that time was only one gram, with no immediate prospects of more.Indium seldom occurs in a mineral in quantities over 0.1 per ccnt.

4. Indium burns in air with a blue flame to form the scsquioxidc, In₂O₃.

5. The other halides (InX and InX₂, where X is a galogen) have been prepared, with the possible exceptions of InF and InF₂. Only the halides, InX₃, are stable in the presence of water. There are three tri-fluorides of indium, the hydrates of the compositions InF₃·3H₂O and InF₃·9H₂O and the anhydrous salt, InF₃.

6. According to one of them, indium-bearing zinc metal was treated with a quantity of dilute H₂SO₄which would dissolve almost all the material, leaving a residue of zinc. On this residue there was collected a spongy mass composed of lead, copper, cadmium, tin, arsenic, iron, and indium.

7. Characteristic spectral blue lines from indium occurbetween 451.1mμ and 410.1 mμ