Answer:
The independent variable would be the type of sunscreen. Hope this helps! :)
The balanced half reactions are
4 Fe2+ ====> 4 Fe3+ + 4 e-
<span>MnO42- + 8 H+ + 4 e- ===> Mn2+ + 4 H2O
The net ionic equation is
4 Fe2+ + </span>MnO42- + 8 H+ ===> 4 Fe3+ + Mn2+ + 4 H2O<span />
Option B.
C (activation energy) would decrease meaning that the catalyst provides an alternative path where lower activation energy is needed for a reaction to take place.
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N(CaCO3)=m÷M
m being the mass of the sample and M being the molar mass of the compound; Molar mass is to be obtained by adding the atomic masses of all the elements in the compound.
therefore,
n(CaCO3)=m÷M
=28g÷100 g.mol
=0.28 mol
therefore, there are 0.28 moles in 28g of Calcium Carbonate.