Answer:
% purity of limestone = 96.53%
Explanation:
Question (4).
Weight of impure CaCO₃ = 25.9 g
Molecular weight of CaCO₃ = 40 + 12 + 3(16)
= 100 g per mole
We know at S.T.P. number of moles of CO₂ = 1 and volume = 22.4 liters
From the given reaction, 1 mole of CaCO₃ reacts with 1 mole or 22.4 liters of
CO₂.
∵ 22.4 liters of CO₂ was produced from CaCO3 = 100 g
∴ 1 liter of CO₂ will be produced by CaCO₃ = 
∴ 5.6 liters of CO₂ will be produced by CaCO₃ = 
= 25 g
Therefore, % purity of CaCO₃ = 
= 
= 96.53 %
Answer:
The activation energy is 164.02 kJ/mol
Explanation:
Log (k2/k1) = Ea/2.303R × [1/T1 - 1/T2]
k1 = 8.9×10^-4 s^-1
k2 = 9.83×10^-3 s^-1
R = 8.314 J/mol.K
T1 = 540 K
T2 = 578 K
Log (9.83×10^-3/8.9×10^-4) = Ea/2.303×8.314 × [1/540 - 1/578]
1.043 = 6.359×10^-6Ea
Ea = 1.043/6.359×10^-6 = 164020 J/mol = 164020/1000 = 164.02 kJ/mol
Answer:
1. Percentage composition of: Na = 42%; P = 19.0%; O = 39%
2. Simplest formula of compound is PbO₂
3. (i) 2Cu(NO₃) ---> 2CuO + 2NO₂ + 3O₂
(ii) 2C₂H₆ + 7O₂ ---> 4CO₂ + 6H₂O
(iii) Mg₃N₂ + 6H₂O ---> 3Mg(OH)₂ + 2NH₃
4. 48 g of MG will react with 2 moles of Cl₂
5. 0.288 g of SO2 will be produced from the combustion of 0.331 g P₄S₃ in excess O₂
6. 12.8 g of nitric oxide can be produced from the reaction of 8.00 g NH₃ with 17.0 g O₂
7. The stock acid solution should be diluted to 6000 mL or 6.0 L
Explanation:
The full explanation is found in the attachments below
The metal roof is most likely made of copper.
Copper turns green over an extended period of time when exposed to water. For example, The Statue of Liberty is made of copper and was once a bronze color. Now, it is green, similar to the roof