Answer:
2 PO₄³⁻(aq) + 3 Fe²⁺(aq) ⇒ Fe₃(PO₄)₂
Explanation:
Let's consider the complete ionic equation between the ions present. It includes all the ions and the insoluble compounds (Fe₃(PO₄)₂ is insoluble).
Na⁺(aq) + 2 PO₄³⁻(aq) + 3 Fe²⁺(aq) + NO₃⁻(aq) ⇒ Fe₃(PO₄)₂ + Na⁺(aq) + NO₃⁻(aq)
The net ionic equation includes only the ions that participate in the reaction (not spectator ions) and the insoluble compounds.
2 PO₄³⁻(aq) + 3 Fe²⁺(aq) ⇒ Fe₃(PO₄)₂
Density = Mass / Volume
10.5 = 500 / x
10.5x = 500
x = 50 cm^3 (1 sig fig) volume of the sphere
Volume of a sphere = 4/3 pi r^2
pi = 3.14 r = radius
50 = 4/3 pi r^3
50•3/4 = pi r^3
37.5 = pi r^3
37.5/pi = r^3
11.9 = r^3
cube root(11.9) = r
2.3 = r
Diameter = 2•radius
Diameter = 2 • 2.3
Diameter = 5 cm (1 sig fig) diameter
Answer:
107g
Explanation:
Magnesium fluoride (MgF₂) has a molecular mass of:
Mg: 24,305 g/mol × 1 = 24,305 g/mol
F: 18,998 g/mol × 2 = 37,996 g/mol
MgF₂ = 24,305g/mol + 37,996g/mol = 62,301g/mol. That means the mass of 1,72 mol of MgF₂ is:
1,72 mol F₂ × (62,301g / 1mol) = <em>107g</em>
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I hope it helps!
Out of those ones, im sure its c. It's definitely not b or d. It allows motion but also protects vital organs. :)
