Odobnoma fanidan 4-sinflar uchun test savollari I variant

9 SINF 2 BLOK Kimyo 2-variant.

1.D.I.Mendeleevning davriy jadvalida nechta metall bor?

A.22 B.97 S 119 D.118

2.Nisbiy atom massasi 79,916 bo’lgan tabiiy bromdagi ⁷⁹Br va ⁸¹Br izotoplarining foiz miqdorini hisoblab toping.

A.45,8:54,2 B.50:50 S.54,2:45:8 D.25:75

3.K₂Cr₂O₇ dagi Cr ning oksidlanish darajasini aniqlang.

A.+3 B. +6 S. +4 D.-6

4.Ishqoriy yer metallar berilgan qatorni ko’rsating.

A.Zn,Cd,Hg B.Li,Na, K S.K,Ca,Li D.Be,Mg,Ca

5.Ca kim tomonidan nechanchi yilda kashf etilgan?

A.G.Devi,1808 B.G.Devi 1807

S. J.Blek,1755 D. D.I.Mendeleev,1869

6.Quyidagi keltirilgan yadro reaksiyasi natijasida qaysi yangi element hosil bo’ladi? ²³⁵U→7α+7β+X

A.Lu B.La S.At D.Mg