ХИМИЯ Определите валентности в следующих соединениях:
а) Mn2O7 б) SO2 в) Cu2O г) Al3N2
2. Определите валентность у следующих бинарных соединений, расставьте индексы и запишите названия:
а) SiH г) BeN
б) NO д) CaF
в) AlS е) MgI

3. Составьте формулы бинарных соединений по их названиям:
а) фторид алюминия
б) хлорид лития
в) карбид кальция
г) силицид калия

Ilove playing with the ball, and i love football the most. this is a very entertaining game, full of excitement. she came to us from england, although in ancient egypt and the maya had similar ball games. today, football - the most common type of sport in the world. millions of people are engaged in their spare time, and indeed billions watching the world championships. professional players, soccer stars, have become idols of entire peoples. you can call diego maradona, paolo maldini, ronaldo, zinedine zidane, andrew arashavina, andriy shevchenko. this sport develops speed, quickness, accuracy, reaction and endurance. the players are very seasoned people, because they chase the ball in the outdoors from early spring to late autumn. football is a team game and develop cohesion and team spirit.