Answer:
Explanation:
When the amount of H2O2 is doubled while KI is kept constant, the rate of reaction doubles.
When the amount of KI is doubled and the amount of H2O2 is halved, the rate stays nearly constant.
2H2O2 (aq) → O2(g) + 2H2O (l) ------------- first order kinetics reaction.
Catalysts are KI, FeCl3 only, KCl is not a catalyst. Order: KI < MnO2 < Pb < FeCl3.
H2O2 + I– -> IO– + H2O (Step 1)
H2O2 + IO– -> I– + H2O + O2 (Step 2)
It can be seen that the iodine ion (provided by the KI solution) is a product as well as a reactant.
02(g)2Fe? (aq) + 2 H(a) 2 H 2 Fe3 (aq) H2O2(aq) + 2 Fe,Taq) H02(aq) 2 Fe (aq) 2 H (aq)
Chemical science deals with mater like compound mater
From the reaction between Cu and HNO₃, the formed gas is NO₂ instead of NO₃. Hence the correct balanced equation would be,
Cu(s) + 4HNO₃(aq) → Cu(NO₃)₂(aq) + 2NO₂(g) + 2H₂O<span>(l)
Here, Cu goes to </span>Cu(NO₃)₂ by changing its oxidation number from 0 to +2 while NO₃⁻ goes to NO₂ by reducing its oxidation state from +5 to +4 . Hence Cu is oxidized by HNO₃ in the reaction.
The molar mass of a substance/chemical is the mass of the sample substance divided by the amount of substance in that sample.
Explanation:
- In order to calculate the atomic mass of a substance we first obtain the atomic weight of the substance from the periodic table.
- Then we count the number of atoms of the substance and multiply it with the individual atomic mass.
Molar mass of Citric Acid ( H3C6H5O7) is 192.1235 g/mol
It is calculated as :
Molar mass of C₆H₈O₇ = 6(atomic mass of C) + 8(atomic mass of H) + 7(atomic mass of O) = 6(12.0 g/mol) + 8(1.0 g/mol) + 7(16.0 g/mol) = 192.0 g/mol.
Molar mass of baking soda (NaHCO₃) is 84.0 g/mol
Molar mass of NaHCO₃ = (atomic mass of Na) + (atomic mass of H) + (atomic mass of C) + 3(atomic mass of O) = (23.0 g/mol) + (1.0 g/mol) + (12.0 g/mol) + 3(16.0 g/mol) = 84.0 g/mol.
Remember that HCl is a strong acid will dissociate almost 100%
HCl + H₂O --> H₃O⁺ + Cl⁻
pH = -log[H₃O⁺]
pH = -log(0.045) = 1.35
(The rules for sig figs are that if you take the log of a number with x significant figures, then the result should have x significant decimal places.)
The pH is 1.35
