3 Part One. The Predicate

Fluorine
Fluorine, the lightest of the galogens, is the most rcactivc of all the elements, and it forms compounds with all the elements except the lighter inert gases. This great reactivity may be attributed to the large value of its electroncgativity. Substances such as wood and rubber burst into flame when they are held in a stream of fluorine, and even asbestos (a silicate of magnesium and aluminium) reacts vigorously with it and becomes incandcsccnt. Platinum is attacked only slowly by fluorine. Copper and steel can be used as containers for the gas; they are attacked by it, but become coatcd with a thin layer of coppcr fluoride or iron fluoride, which then protects them against further attack.

Because its electroncgativity is greater than that o f any other element, We cannot expect that fluorine could be prepared by reaction of any other element with a fluoride. It could have been made, however, by electrolysis of fluorides, since the oxidizing power (electron affinity) of an electrodc can be increased without limit by increasing the applied voltage. Fluorine was first obtained by the French chemist Henri Moissan (1852-1907) in 1886 by the electrolysis of a solution of KF in liquid HF. The work mustbavc been extremely difficult, for it took him several years of hard experimenting to obtain free fluorine gas.

Mashq 4. Mashq 4. Menga ayting-chi, 9B matndan yangi biror narsa o'rgandingizmi? Agar bilsangiz, unda aniq nima?

Mashq 5. Matnni tematik ravishda ko'pincha n ga bo'ling, har bir qismini sarlavha qo'ying.

Mashq 6. Matn nima haqida ekanligini ayting:

1) ftorning boshqa elementlar bilan bog'lanish qobiliyati; 2) ftorning yuqori reaktivligini nima tushuntiradi; 3) ftorning asbestga ta'siri to'g'risida; 4) ftor qanday birinchi bor olinganligi.

Mashq 7. Ftor ishlab chiqarish imkoniyatlarini tavsiflovchi matndan parchani toping va uni o’zbek tiliga tarjima qiling.