Answer:
0.004522 moles of hydrogen peroxide molecules are present.
Explanation:
Mass by mass percentage of hydrogen peroxide solution = w/w% = 3%
Mass of the solution , m= 5.125 g
Mass of the hydrogen peroxide = x



Mass of hydregn pervade in the solution = 0.15375 g
Moles of hydregn pervade in the solution :

0.004522 moles of hydrogen peroxide molecules are present.
8 H2= 0.90 g , hope that helps
you with your work
Answer:
billion is larger \ part if billion
Answer: It becomes the uncombined element in the product.
Explanation:
The reaction between Zn and HCl is a single displacement reaction according to equation below
Zn + 2HCl —> ZnCl2 + H2
Zn displaces H2 from acid and in the product, hydrogen became the uncombined element.
Answer:
Ksp = 1.07x10⁻²¹
Explanation:
Molar solubility is defined as moles of solute can be dissolved in 1L.
Ksp for NiS is defined as:
NiS(s) ⇄ Ni²⁺(aq) + S²⁻(aq)
Ksp = [Ni²⁺] [S²⁻]
As molar solubility is 3.27x10⁻¹¹M, concentration of [Ni²⁺] and [S²⁻] is 3.27x10⁻¹¹M for both.
Replacing:
Ksp = [3.27x10⁻¹¹M] [3.27x10⁻¹¹M]
<em>Ksp = 1.07x10⁻²¹</em>
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