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\(a.2Na+2H_2O->2NaOH+H_2\\ n_{Na}=\dfrac{1,2\cdot10^{23}}{6\cdot10^{23}}=0,2mol=n_{NaOH}\\ n_{H_2}=\dfrac{1}{2}\cdot0,2=0,1mol\\ N_{NaOH}=N_{Na}=1,2\cdot10^{23}\left(PT\right)\\ N_{H_2}=0,1\cdot6\cdot10^{23}=0,6\cdot10^{23}\left(PT\right)\\ b.m_{NaOH}=40\cdot0,2=8g\\ m_{H_2}=2\cdot0,1=0,2g\\ c.V_{H_2}=22,4\cdot0,1=2,24L\)
PT: \(2Na+2H_2O\rightarrow2NaOH+H_2\)
\(n_{H_2}=\dfrac{30,24}{24,79}\approx1,22\left(mol\right)\)
a, \(m_{H_2}=1,22.2=2,44\left(g\right)\)
b, Theo PT: \(n_{Na}=2n_{H_2}=2,44\left(mol\right)\)
\(\Rightarrow A_{Na}=2,44.6.10^{23}=14,64.10^{23}\) (nguyên tử)
\(m_{Na}=2,44.23=56,12\left(g\right)\)
c, \(n_{NaOH}=2n_{H_2}=2,44\left(mol\right)\)
\(\Rightarrow A_{NaOH}=2,44.6.10^{23}=14,64.10^{23}\) (phân tử)
\(\Rightarrow m_{NaOH}=2,44.40=97,6\left(g\right)\)
a)PTHH: Na+H2O---> NaOH+H2
b)nNa= \(\dfrac{m}{M}=\dfrac{2,3}{23}=0,1\left(mol\right)\)
=>nNa=nH2=0,1 (mol)
=>VH2=n.22,4=0,1.22,4=2,24(l)
c)nNa=nH2O=nNaOH=0,1 (mol)
=>mH2O=0,1.18=1,8(g)
d)mNaOH=0,1.(23+16+1)=4(g)
Học tốt !
a, \(2Na+2H_2O\rightarrow2NaOH+H_2\)
b, \(n_{Na}=\dfrac{2,3}{23}=0,1\left(mol\right)\)
Theo PT: \(n_{H_2}=\dfrac{1}{2}n_{Na}=0,05\left(mol\right)\Rightarrow V_{H_2}=0,05.22,4=1,12\left(l\right)\)
c, \(n_{H_2O}=n_{Na}=0,1\left(mol\right)\Rightarrow m_{H_2O}=0,1.18=1,8\left(g\right)\)
d, \(n_{NaOH}=n_{Na}=0,1\left(mol\right)\Rightarrow m_{NaOH}=0,1.40=4\left(g\right)\)
PT: \(CaCO_3\underrightarrow{t^o}CaO+CO_2\)
Ta có: \(n_{CaO}=\dfrac{7}{56}=0,125\left(mol\right)\)
a, Theo PT: \(n_{CaCO_3}=n_{CaO}=0,125\left(mol\right)\)
\(\Rightarrow A_{CaCO_3}=0,125.6,10^{23}=0,75.10^{23}\) (phân tử)
\(m_{CaCO_3}=0,125.100=12,5\left(g\right)\)
b, \(n_{CO_2}=n_{CaO}=0,125\left(mol\right)\)
\(A_{CO_2}=0,125.6.10^{23}=0,75.10^{23}\) (phân tử)
\(m_{CO_2}=0,125.44=5,5\left(g\right)\)
c, \(V_{CO_2}=0,125.24,79=3,09875\left(l\right)\)
\(n_{CO_2}=\dfrac{71,68}{22,4}=3,2\left(mol\right)\)
=> \(m_{CO_2}=3,2.44=140,8\left(g\right)\)
PTHH: CaCO3 + 2HCl --> CaCl2 + CO2 + H2O
3,2<---6,4<-------3,2<----3,2
\(m_{CaCO_3}=3,2.100=320\left(g\right)\)
Số phân tử CaCO3 = 3,2.6.1023 = 19,2.1023 (phân tử)
\(m_{HCl}=6,4.36,5=233,6\left(g\right)\)
Số phân tử HCl = 6,4.6.1023 = 38,4.1023 (phân tử)
\(m_{CaCl_2}=3,2.111=355,2\left(g\right)\)
Số phân tử CaCl2 = 3,2.6.1023 = 19,2.1023 (phân tử)
\(n_{H_2SO_4}=\dfrac{m}{M}=\dfrac{12,25}{98}=0,125mol\)
\(2Na+H_2SO_4\rightarrow Na_2SO_4+H_2\)
0,25 0,125 0,125 ( mol )
\(m_{Na}=n.M=0,25.23=5,75g\)
\(m_{Na_2SO_4}=0,125.142=17,75g\)
\(n_{H_2O}=\dfrac{14,4}{18}=0,8mol\)
\(2Na+2H_2O\rightarrow2NaOH+H_2\)
0,8 0,8 0,8 ( mol )
\(m_{Na}=0,8.23=18,4g\)
\(m_{NaOH}=0,8.40=32g\)
Số mol của nước là:
nH2O=14,4/18=0,8(mol)
PTHH: Na+H2O→NaOH+1/2H2
0,8 0,8 0,8 0,4 ( mol)
a) Thể tích khí Hidro tạo thành(ĐKTC) là:
VH2=0,4*22,4= 8,96(l)
b) Khối lượng Natri là:
mNa=0,8*23 =18,4(g)
Khối lượng Bazơ tạo thành sau phản ứng là:
mNaOH=0,8*40=32(g)
a) \(n_{Al}=\dfrac{5,4}{27}=0,2\left(mol\right)\)
PTHH: \(2Al+3H_2SO_4\rightarrow Al_2\left(SO_4\right)_3+3H_2\)
0,2--->0,3-------->0,1----------->0,3
b) `V_{H_2} = 0,3.22,4 = 6,72 (l)`
c) `m_{H_2SO_4} = 0,3.98 = 29,4 9g)`
d) \(n_{CuO}=\dfrac{16}{80}=0,2\left(mol\right)\)
PTHH: \(CuO+H_2\xrightarrow[]{t^o}Cu+H_2O\)
Xét tỉ lệ: 0,2 < 0,3 => H2 dư
PT: \(2Na+2H_2O\rightarrow2NaOH+H_2\)
Ta có: \(n_{NaOH}=\dfrac{14,8}{40}=0,37\left(mol\right)\)
a, Theo PT: \(n_{Na}=n_{NaOH}=0,37\left(mol\right)\)
\(\Rightarrow A_{Na}=0,37.6.10^{23}=2,22.10^{23}\) (nguyên tử)
\(m_{Na}=0,37.23=8,51\left(g\right)\)
b, \(n_{H_2}=\dfrac{1}{2}n_{NaOH}=0,185\left(mol\right)\)
\(\Rightarrow A_{H_2}=0,185.6.10^{23}=1,11.10^{23}\) (phân tử)
\(m_{H_2}=0,185.2=0,37\left(g\right)\)
c, \(V_{H_2}=0,185.24,79=4,58615\left(l\right)\)