Answer:
Have the same number of electrons in their outer energy levels
Explanation:
Elements in the same group have similar chemical properties because they have the same number of valence electron(s) in their outermost shell.
Chlorine and Iodine have similar chemical properties because they have the same number of valence electron in their outermost shell. This can be seen from their electronic configuration as shown below:
Cl (17) => 1s² 2s²2p⁶ 3s²3p⁵
I (53) => [Kr] 4d¹⁰ 5s²5p⁵
From the above illustration:
Outer shell of Cl (3s²3p⁵) = 2 + 5 = 7 electrons
Outer shell of I (5s²5p⁵) = 2 + 5 = 7 electrons
Since they have the same number of valence electrons, therefore, they will have similar chemical properties.
The correct answer for box C is coefficient
The reaction equation:
2H₂S + SO₂ → 3S + 2H₂O
Calculating moles of H₂S:
10 / 34 = 0.29
Moles of SO₂:
10 / 64 = 0.15
Stoichometric amounts of each reactant are present so the moles of S formed will be:
0.15 x 3 = 0.45
Mass of S formed = 14.4 grams
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