The electrons begin at the lowest level, and then fills up until it reaches the highest level, and completely fills the outer shell.
x + y = 100
0.10x + 0.45 y =25
eliminate
x + y = 100
x + 4.5 y = 250
-3.5 y = -150
y = 42.85
x = 57.15
hope this helps
Potassium Iodide or KI is an ionic compound and dissolves to water since the two are polar substances. Like dissolves like. As KI is dissolved into water, the KI molecules dissociates into ions, the K+ and I- ions. Water molecules can stabilize these ions. The K+ ions attracts the negative side of H2O molecules which is the oxygen side while the I- ions attracts the positive side of H2O molecules or the hydrogen side.
Hi friend
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Your answer
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Water = H2O
Number of molecules in one mole of water = 6.022 × 10²³ [Avogadro's constant]
Given number of molecules = 2.52 × 10²³
So,
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Number of moles =

HOPE IT HELPS