a.
MgO+H2SO4->MgSO4+H20
0,13.....0,13.......0,13
Mg+H2SO4->MgSO4+H2
0,2...0,2...........0,2........<-.0,2
mMg=24.0,2=4,8g=>%mMg=
%mMgO=
mMgO=10-4,8=5,2g=>mMgO=5,2/40=0,13mol
CM dd H2SO4=(0,13+0,2)/0,5=
CM dd MgSO4=(0,13+0,2)/0,5=
c1: Dùng ĐLBTKL
Bạn tự viết pt nha
nCo2=4,48/22,4=0,2mol=>mCO2=0,2.44=8,8g
nHCl=2nCO2=2.0,2=0,4mol=>mHCl=0,4.36,5=14,6g
nH2O=nCo2=0,2mol=>mH2O=0,2.18=3,6g
m muối=18,4+14,6-8,8-3,6=20,6g
V. Read the text and then do the tasks that follow. (2.0/10)
Have you ever wondered what the weather is like in other places around the world? Today, I’d like to talk about the changing seasons in my city. The winter season usually begins in December and ends in early March. The coldest month...
I. Choose the word that has the underlined part pronounced differently from the rest. (1.0/10)
1. A. monkey B. donkey C. grey D. key
2. A. asked B. needed C. lasted D. painted
3. A. agent...
AxOy+yCO->xA+yCO2
..........
Hỗn hợp khí B: CO dư, CO2
Gọi x, y lần lượt là số mol CO2 và CO dư
nCO=49,28/22,4=2,2mol
Có:
(44x+28y)/(x+y)=19,49.2
<=>44x+28y=38,98x+38,98y
<=>5,02x-10,98y=0
@Hồng Nhật giúp em với
a. Nai ???
b.
-cho dd naoh dư
+ tạo kt keo trắng rồi tan trong kiềm dư: alcl3
Alcl3+3naoh->al(oh)3+3nacl
Al(oh)3+naoh->naalo2+2h2o
+tạo kt keo trắng:ZnSO4
ZnSO4+2NaOH->Zn(OH)2+Na2SO4
+ko ht:agno3,na2co3
-cho dd hcl dư vào hh AgNO3 và na2co3
+sinh ra khí:na2co3
Na2co3+2hcl->2nac+co2+h2o
+tạo.kt...
1.Cathy hid the presents so that nobody could see them.
2.We had the party in a large hall so that people could dance.
3.Dick arrived early so that he could get a good seat.
4.I changed seat so that I could see better.
5.We took some sandwiches so that we couln't feel hungry.
6.Harry wore a...