1000+2000+3000+4000+...+9000+10000=55000

11

tích đi mình tích lại

-10, tick nha

xuong dat,vao tai,theo huong la co vay

Ta có: mKCl thực tế = 61.25 . 80 :100 =49g

------> n KCl = 49 : 74,5 = 0,65 mol

a) 2KClO3 -----> 2KCl + 3O2

2 2 3

0,65 <-------- )0,65

mKClO3 = 0,65 . 122,5 = 79,625 mol

n HCl = 3,56 : 36,5 = 0,1 mol

Fe + 2HCl ------> FeCl2 + H2 Cu +HCl ------> Không phản ứng

1 2 1 1

0,05<---- 0,1 ------------> 0,05

mFe = 0,05 . 56 = 2,8 g

mCu = 10 - 2,8 = 7,2 g

%m Fe = 2,8 . 100 :10 = 28%

%mCu = 7,2 .100 :10 =72 %

VH2 = 0,05 .22,4 =1,12l

1) That book was published one year ago

2) The magazines are put on the shelf in the right corner of the library

3) These toys are sold in Disneyland and Hong Kong

4) These old clothes are collected by the poor children

5)These reports will be finished by him at five o' clock

6) Nam said he attended in the lecture in that night

mO2 = 12 - 7,2 = 4.8g -----> nO2 = 4,8 : 32 = 0,15 mol

2R + O2 ------> 2RO (nhiệt độ)

2 1 2

0,3<-----0,15

nR= 0,3 mol

mR = 7,2 g

---------> MR = 7,2 : 0.3 = 24 g ( Mg )

Vậy R là Mg