Câu 5:

Ở 90 độ C, 100g   -     50g     -        150g dd

                   450g         225g    -        675g dd

Gọi số mol CuSO4.5H2O là x (mol)

\(\rightarrow m_{CuSO_4}=160x\left(g\right)\rightarrow m_{CuSO_4\left(còn\right)}=225-160x\left(g\right)\)

\(m_{H_2O}=180x\left(g\right)\rightarrow m_{H_2O\left(còn\right)}=450-180x\left(g\right)\)

Ở 10 độ C, 100 g nước thu được 36g CuSO4.

                 450-180x(g)             225-160x(g)

\(\rightarrow\left(450-180x\right).36=100.\left(225-160x\right)\)

\(\rightarrow16200-6480x=22500-16000x\)

\(16000x-6480x=22500-16200\)

\(\rightarrow x\approx0,662\)

\(m_{CuSO_4.5H_2O}=0,662.\left(160+180\right)=225\left(g\right)\)

\(1.\\ \left(a\right)n_{Cu}=\dfrac{12,8}{64}=0,2\left(mol\right)\\ n_{CaCO_3}=\dfrac{50}{100}=0,2\left(mol\right)\\ n_{Cl_2}=\dfrac{6,1975}{24,79}=0,25\left(mol\right)\\ n_{CO_2}=\dfrac{7,437}{24,79}=0,3\left(mol\right)\\ n_{HCl}=0,2.2=0,4\left(mol\right)\\ n_{NaCl}=0,5.0,5=0,25\left(mol\right)\\ \left(b\right)m_{MgO}=0,15.40=6\left(g\right)\\ m_{Cl_2}=\dfrac{6,1975}{24,79}\cdot71=17,75\left(g\right)\\ \left(c\right)V_{hh}=\left(0,15.24,79\right)+\left(0,35.24,79\right)=12,395\left(l\right)\)

\(2,\\ \left(a\right)C_{\%NaCl}=\dfrac{40}{40+160}\cdot100=20\%\\ \left(b\right)C_{\%A}=\dfrac{0,5}{50}\cdot100=1\%\\ 3,\\ \left(a\right)C_{M\left(MgCl_2\right)}=\dfrac{0,5}{2,5}=0,2M\\ \left(b\right)C_{M\left(BaCl_2\right)}=\dfrac{0,2}{0,6:1,2}=0,4M\)

\(4,\\ \left(a\right)Fe+2HCl\xrightarrow[]{}FeCl_2+H_2\\ n_{Fe}=\dfrac{11,2}{56}=0,2\left(mol\right)\\ n_{H_2}=n_{Fe}=0,2mol\\ V_{H_2}=0,2.24,79=4,958\left(g\right)\)

(b) mik nghĩ là tính m kim loại sau pư

\(CuO+H_2\xrightarrow[]{}Cu+H_2O\\ n_{Cu}=n_{H_2}=0,2mol\\ m_{Cu}=64.0,2=12,8\left(g\right)\)

a) sửa CaO

`n_(CaO)=(14/56)=0,25`mol

b)

`n_(CO_2)= 66/44=1,5` mol

c)

`n_(H_2)= (3,36)/22,4=0,15 mol`

d)

`n_(SO_3)= (22,4)/22,4=0,1 mol`

e)

`n_(Mg)=(3,55.10^23)/(6,02.10^23)=0,589mol.`

f)

tương tự e)

\(a,n_{CO_2}=\dfrac{V_{\left(đktc\right)}}{22,4}=\dfrac{1,2395}{22,4}=\dfrac{2479}{44800}\left(mol\right)\)

\(b,Theo.CTHH:CO_2\\ \Rightarrow n_C=n_{CO_2}=\dfrac{2479}{44800}\left(mol\right)\\ n_O=2n_{CO_2}=2.\dfrac{2479}{44800}=\dfrac{2479}{22400}\left(mol\right)\\ \Rightarrow m_C=n.M=\dfrac{2479}{44800}.12=\dfrac{7437}{12200}\left(g\right)\\ m_O=n.M=\dfrac{2479}{22400}.16=\dfrac{2479}{1400}\left(g\right)\)

\(c,số.phân.tử.CO_2:n.6.10^{23}=\dfrac{2479}{44800}.6.10^{23}=\dfrac{23240625.10^{16}}{7}\)

a) \(n_{CO_2}=\dfrac{V}{22,4}=\dfrac{1,2395}{22,4}=0,05\left(mol\right)\)

b) \(m_{CO_2}=0,05.44=2,2\left(g\right)\)

c) Số phân tử CO2 là: 0,05.6.10²³ = 0,3.10²³ = 3.10²² (phân tử)

a,\(n_{CO_2}=\dfrac{1,2395}{24,79}=0,05\left(mol\right)\)

b, \(m_{CO_2}=n_{CO_2}.M_{CO_2}=0,05.44=2,2\left(g\right)\)

c, Số phân tử CO₂=\(n_{CO_2}.6.10^{23}=0,05.6.10^{23}=3.10^{22}\)

Đúng 

a, \(n_{CO_2}=\dfrac{1,2395}{22,4}=0,055mol\)

\(b,m_{CO_2}=0,055.44=2,42g\)

\(c,Số.phân.tử.CO_2=0,055.6.10^{23}=3,3.10^{22}\) phân tử

a) \(n_{CO_2}=\dfrac{1,2395}{22,4}\approx0,05\left(mol\right)\)

b) \(m_{CO_2}=0,05.44=2,2\left(g\right)\)

a) \(n_{CO_2}=\dfrac{1,2395}{24,79}=0,05\left(mol\right)\)

b) \(m_{CO_2}=0,05.44=2,2\left(g\right)\)

c) Số phân tử CO₂ = 0,05.6.10²³ = 0,3.10²³

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