Giup tui vs :(
Dot chay hoan toan 3,1g P trg KK
a, Vt PTHH xay ra
b, Tinh P2O5 thu dk?
C, Tinh Vkk(dktc). bt trg kk â chiem 20%the tich
dot chay hoan toan 1,68 lit (dktc) khí metan (ch4) sinh ra khi cacbonic va nuoc
a, khoi luong khi cacbonic va nuoc sinh ra
b the tich khong khi can de dot chay luong khi metan tren biet khi o2 chiem 20% the tich khong khi
a)n CH4=1,68/22,4=0,075(mol)
CH4+2O2---->CO2+2H2O
0,075----0,15------0,075----0,15(mol)
m CO2=0,075.44=3,3(g)
m H2O=0,15.18=2,7(g)
b) V O2=0,15.22,4=3,36(l)
V kk=3,36.5=16,8(l)
dot chay 6,72 gam Magie trong binh dung tich 14 lit chua kk thu dc a g magie oxit .tinh a biet oxi chiem 1/5 v kk hieu suat phan ung la 85%
ta có PTHH
2Mg + O2 \(\rightarrow\) 2MgO
Vo2 = 1/5 Vkk =1/5 .14 =2.8(l)
=> nO2= V/22.4 = 2.8/22.4=0.125
Có: H= mMg(PƯ) / mMg(ĐB) . 100%=85%
=> mMg(PƯ)= 85% : 100% . 6.72=5.712 (g)
=> nMg(PƯ)= m/M = 5.712/24=0.238(mol)
Lập tỉ lệ:
\(\frac{n_{Mg\left(ĐB\right)}}{n_{Mg\left(PT\right)}}=\frac{0.238}{2}\)=0.119 < \(\frac{n_{O2\left(ĐB\right)}}{n_{O2\left(PT\right)}}=\frac{0.125}{1}=0.125\)
=> sau PƯ : Mg hết và O2 dư
Theo PT => nMgO = n Mg = 0.238 (mol)
=> mMgO = n .M = 0.238 . 40 =9.52 (g)
=> a=9.52g
Bài 1:
PT: \(3Fe+2O_2\underrightarrow{t^o}Fe_3O_4\)
a, Ta có: \(n_{O_2}=\dfrac{4,48}{22,4}=0,2\left(mol\right)\)
Theo PT: \(n_{Fe}=\dfrac{3}{2}n_{O_2}=0,3\left(mol\right)\)
\(\Rightarrow m_{Fe}=0,3.56=16,8\left(g\right)\)
b, Theo PT: \(n_{Fe_3O_4}=\dfrac{1}{2}n_{O_2}=0,1\left(mol\right)\)
\(\Rightarrow m_{Fe_3O_4}=0,1.232=23,2\left(g\right)\)
Bài 2:
PT: \(2KMnO_4\underrightarrow{t^o}K_2MnO_4+MnO_2+O_2\)
Ta có: \(n_{KMnO_4}=\dfrac{15,8}{158}=0,1\left(mol\right)\)
Theo PT: \(n_{O_2}=\dfrac{1}{2}n_{KMnO_4}=0,05\left(mol\right)\)
\(\Rightarrow V_{O_2}=0,05.22,4=1,12\left(l\right)\)
Bạn tham khảo nhé!
a, Tinh khoi luong, the tich (o dktc) va so phan tu CO2 co trong 0,75 mol khi CO2 ?
b, Dot chay hoan toan m gam chat X can dung 0,2 mol khi O2 thu duoc 2,24 lit khi CO2 (o dktc) va 3,6 gam H2O
a, Viet so do phan ung ?
b, Tinh khoi luong cua khi Oxi va khi CO2 ?
c, Tinh khoi luong cua chat X ?
a) mCO2 = n.M = 0,75.44 = 33 gam
V = 0,75.22,4 = 16,8 lít
Số phân tử trong 0,75 mol = 0,75.6,022.1023 =4,5165.1023 phân tử
b) X + O2 ---> CO2 + H2O
mO2 = 0,2.32 = 6,4 gam
nCO2 = \(\dfrac{2,24}{22,4}\)= 0,1 mol => mCO2 = 0,1.44 = 4,4 gam
Áp dụng định luật bảo toàn khối lượng : mX + mO2 = mCO2 + mH2O
=> mX = 4,4 + 3,6 - 6,4 = 1,6 gam
tinh the tich khi oxi va the tich khong khi [dktc] can thiet de dot chay:1 mol cacbon;1.5 mol photpho.cho biet oxi chiem 20% the tich khong khi.
a) ta có PTHH: O2 + C \(\underrightarrow{t^0}\) CO2
theo gt: nC =1(mol)
theo PTHH: nO2=nC=1(mol)
\(\Rightarrow\) VO2=1*22,4=22,4(lit)
\(\Rightarrow\)Vkk=\(\frac{V_{O2}\cdot100}{20}=\frac{22,4\cdot100}{20}=112\left(lit\right)\)
b)ta có PTHH : 4P+5O2\(\underrightarrow{t^0}\) 2P2O5
theo gt: nP=1,5(mol)
\(\Rightarrow\)nO2=5/4*nP=5/4*1,5=1,875(mol)
\(\Rightarrow\)VO2=22,4*1,875=42(lit)
\(\Rightarrow\)Vkk=\(\frac{42\cdot100}{20}=210\left(lit\right)\)
chia V lit hon hop thanh 2 phan bang nhau
- dot chay hoan toan phan thu nhat bang oxi, sau do dan qua nuoc voi trong du thu duoc 20 gam chat ket tua trang
- dan phan thu hai di qua bot CuO du dun nong phan ung xong thu duoc 19.2 gam Cu
a) viet PTHH
b Xac dinh V(dktc)
c tinh the tich H2 da tham gia
giai giup voi nha can nhieu bai do neu ai mau den sang mai minh tick cho (Thank You very much)
dot chay 8,4 g sat trong binh chua oxi thu duoc oxit sat tu Fe3o4
a. viet pt phan ung xay ra
b. tinh the tich khi oxi can dung(o dktc)
c. tinh khoi luong cua oxi sat tu sau phan ung
3Fe+2O2--->Fe3O4
0,15-0,1------0,05 mol
nFe=8,4\56=0,15 mol
=>VO2=0,15.22,4=3,36 l
=>mFe3O4=0,05.232=11,6 g
3Fe+2O2--->Fe3O4
nFe=8,4\56=0,15 mol
theo pt nO2=0,15 .2\3 =0,1 mol
=>VO2=0,1.22,4=22,4l
theopt nFe3O4 =0,15.1\3 =0,05 mol
=>mFe3O4=0,05.232=11,6 g
Dot chay hoan toan mot thanh nhôm trong khong khi. Sau phan ung thu dc 20,4 gam nhom oxit.
a) tinh khoi luong thanh nhom biet rang trong thanh nhom chua 15% tap chat trơ ko cháy
b) tinh the tich khong khi
Giup mik voi
\(4Al+3O_2\rightarrow2Al_2O_3\)
\(n_{Al_2O_3}=\frac{20,4}{102}=0,2mol\)
\(n_{Al\left(lt\right)}=2.n_{Al_2O_3}=2.0,2=0,4mol\)
\(m_{Al\left(lt\right)}=0,4.27=10,8g\)
\(m_{Al\left(tt\right)}-\frac{15}{100}.m_{Al\left(tt\right)}=10,8\)
\(\Rightarrow m_{Al\left(tt\right)}=\frac{216}{17}g\)
b) \(n_{O_2}=\frac{3}{2}.n_{Al_2O_3}=\frac{3}{2}.0,2=0,3mol\)
\(V_{O_2}=0,3.22,4=6,72l\)
\(V_{kk}=6,72.5=33,6l\)
Cai phan lua chon la mik ấn nhầm, ai giup mik di
DAN 2,8 L "DKTC" HON HOP GOM METAN VA ETILEN DI QUA DUNG DICH BROM DU THI THAY CO 4 BROM DA PHAN UNG
A)TINH KHOI LUONG MOI KHI VA THANH PHAN PHAN TRAM MOI KHI CO TRONG HON HOP
B)TINH THE TICH KHONG KHI CAN DUNG' DKTC" DE DOT CHAY HOAN TOAN HON HOP TREN