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

2) Pete scratch one's head. He looks puzzled

3) Alex tap's one food. He seems to be impatient

4) Helen bite one's lip. She looks worred.

5) Gus cross one's arms .He looks bored

6)John shrug one' shoulders. He looks unsure

7) Laura clench one's teeth.She looks furious

8) Tom raise one's eyebrows. He seems to be surprised.

Объяснение:

Vasya fumble one's sleeve. He looks worried.

Tanya straightens her hair. She looks brooding.

Petya nibbles a pencil. He looks nervous.

Lena looks out the window. She looks boring.

Slava scratches his head. He looks puzzled.

Sasha cross one's arms .She looks  dissatisfied

Nika shrug one' shoulders. She looks unsure

Nastya tap one's hands on the table. She seems impatient

Yegor clench one's teeth.He looks furious  

Vladimir raise one's eyebrows. He seems to be surprised.

Подставьте имена своих одноклассников

In my classroom a lot of friends are: Misha, Sasha, Olya, Gleb and Max. Misha is very smart sometimes helps me with my homework. We are friends from the first class. He loves to draw with his friends. Sasha is not smart, but sometimes he can tell a lot of interesting things I know his recently. He is quiet and does not like to talk off-topic. Olya is beautiful in the class and I fell in love with her several times. She is noisy and sometimes angry. Gleb is very strong but he loves dessert. He is my best friend. He is fat but good jokes and can make tales interesting. He likes to rest at lessons.