Answer is: 25.84 milliliters of sodium metal.
Balanced chemical reaction: 2Na + 2H₂O → 2NaOH + H₂.
d(Na) = 0.97 g/mL; density of sodim.
m(NaOH) = 43.6 g; mass of sodium hydroxide.
n(NaOH) = m(NaOH) ÷ M(NaOH).
n(NaOH) = 43.6 g ÷ 40 g/mol.
n(NaOH) =1.09 mol; amount of sodium hydroxide.
From chemical reaction: n(NaOH) : n(Na) = 2 : 2 (1: 1).
n(Na) = 1.09 mol.
m(Na) = 1.09 mol · 23 g/mol.
m(Na) = 25.07 g; mass of sodium.
V(Na) = m(Na) ÷ d(Na).
V(Na) = 25.07 g ÷ 0.97 g/mL.
V(Na) = 25.84 mL.
Acid rain falling on limestone
Answer:
9.86*10^(-3) g
Explanation:
PbSO4 ----> Pb^(2+) + SO4^(2-)
s s
Ksp = s²
s =√Ksp = √(1.8*10^-8) = 1.3*10^(-4) mol/L
The molar solubility PbSO4 = 1.3*10^(-4) mol/L.
2.50 *10^2 mL *1L/10³mL =0.250L
1.3*10^(-4)mol/L *0.250L*303.3 g/mol = 9.86*10^(-3) g
Answer:
The concentration of [Ca²⁺] is 8.47 x 10⁻³ M
Explanation:
We consider the solubility of hydroxyapatite,
Ca₁₀(PO₄)₆(OH)₂ ⇔ 10Ca²⁺ + 6PO₄³⁻ + 2 OH⁻
Assumed that there is <em>a</em> mol of hydoxyapatite disolved in water, yielding <em>10a</em> mol Ca²⁺ of and <em>6a</em> mol of PO₄³⁻
We also have Ksp equation,
Ksp = [Ca²⁺]¹⁰ x [PO₄³⁻]⁶ x [OH⁻]² = 2.34 x 10⁻⁵⁹
⇔ 10a¹⁰ x 6a⁶ x (5.30 x 10⁻⁶)² = 2.24 x 10⁻⁵⁹
⇔ 60a¹⁶ = 2.24 x 10⁻⁵⁹ / 5.30 x 10⁻¹²
⇔ a¹⁶ = 0.007 x 10⁻⁴⁷ = 7 x 10⁻⁵⁰
⇔ a = ![\sqrt[16]{7 . 10^{-50} }](https://tex.z-dn.net/?f=%5Csqrt%5B16%5D%7B7%20.%2010%5E%7B-50%7D%20%7D)
= 8.47 x 10⁻⁴
Hence,
[Ca²⁺] = 10<em>a</em> = 8.47 x 10⁻³ M
