Answer:
Mass = 2.355 g
Explanation:
Given data:
Mass of K₂O needed = ?
Mass of KNO₃ produced = 5.00 g
Solution:
Chemical equation:
K₂O + Ca(NO₃)₂ → CaO + 2KNO₃
Number of moles of KNO₃:
Number of moles = mass/molar mass
Number of moles = 5.00 g/ 101.1 g/mol
Number of moles = 0.05 mol
now we will compare the moles of KNO₃ and K₂O.
KNO₃ : K₂O
2 : 1
0.05 : 1/2×0.05 = 0.025 mol
Mass of potassium oxide needed in gram:
Mass = number of moles × molar mass
Mass = 0.025 mol × 94.2 g/mol
Mass = 2.355 g
The answer is b. the water molecules are more closely packed together in ice than in water <span />
Answer:
2 CO + O2 ———————-> 2 CO2
Mass of CO = 174 g
First change it into moles
No of moles = (mass in grams)/molar mass
Molar mass of CO = 30 g/mol
No of moles of CO = 174/30 = 5.8 mol
2 CO + O2 ———————-> 2 CO2
Equation shows that
2 moles of CO react with moles of O2 = 1 mol
1 mole of CO react with moles of O2 = 1/2
1 mole of CO react with moles of O2 = 0.5 mol
5.8 mole of CO react with moles of O2 =0.5x5.8
5.8 mole of CO react with moles of O2 = 2.9 mol
No of moles of O2 used = 2.9 mol
Then change it into no of molecules
No of molecules of O2 = 2.9x6.02x10^23
No of molecules of O2 used = 17.45x10^23
Explanation: