<span>Net Ionic equation: 3Zn^2+(aq) + 2PO4^3-(aq) ---> Zn3(PO4)2 (s)
hope it helps
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Answer:
81 molecules
Explanation:
The reaction between C5H12 and O2 is a combustion reaction and is represented by the following equation;
C5H12 + 8O2 --> 5CO2 + 6H2O
The ratio of C5H12 to O2 from the above equation is 1 : 8.
Aplying the conditins of the question; 24 molecules each of C5H12 and O2 we have;
3C5H12 + 24O2 --> 15CO2 + 18H2O
This means we have 24 - 3 = 21 molecules of C5H12 that are unreacted.
Total molecules is given as;
3(C5H12) + 24(O2) + 15(CO2) + 18(H2O) + 21(Unreacted C5H12) = 81 molecules
Answer is: the percent by mass of NaHCO₃ is 2,43%.
m(NaHCO₃) = 10 g.
V(H₂O) = 400 ml.
d(H₂O) = 1 g/ml.
m(H₂O) = V(H₂O) · d(H₂O).
m(H₂O) = 400 ml · 1 g/ml.
m(H₂O) = 400 g.
m(solution) = m(H₂O) + m(NaHCO₃).
m(solution) = 400 g + 10 g.
m(solution) = 410 g.
ω(NaHCO₃) = 10 g ÷ 410 g · 100%.
ω(NaHCO₃) = 2,43 %