A barium hydroxide solution is prepared by dissolving 2.29 g of Ba(OH)2 in water to make 46.6 mL of solution. What is the concentration of the solution in units of molarity? Concentration: 0.287 M

The barium hydroxide solution is used to titrate a perchloric acid solution of unknown concentration. Write a balanced chemical equation to represent the reaction between barium hydroxide and perchloric acid.
Chemical Equation:

If 25.5 mL of the barium hydroxide solution was needed to neutralize a 8.99 mL aliquot of the perchloric acid solution, what is the concentration of the acid?
Concentration:

0.287 M

Ba(OH)₂ + 2 HClO₄ ⇒ Ba(ClO₄)₂ + 2 H₂O

1.62 M

Explanation:

Step 1: Calculate the concentration of Ba(OH)₂

We will use the following expression.

[Ba(OH)₂] = mass Ba(OH)₂/ molar mass Ba(OH)₂ × liters of solution

[Ba(OH)₂] = 2.29 g/ 171.34 g/mol × 0.0466 L = 0.287 M

Step 2: Write the balanced neutralization equation

Ba(OH)₂ + 2 HClO₄ ⇒ Ba(ClO₄)₂ + 2 H₂O

Step 3: Calculate the reacting moles of Ba(OH)₂

25.5 mL of 0.287 M Ba(OH)₂ react.

0.0255 L × 0.287 mol/L = 7.32 × 10⁻³ mol

Step 4: Calculate the reacting moles of HClO₄

7.32 × 10⁻³ mol Ba(OH)₂ 2 mol HClO₄/1 mol Ba(OH)₂ = 0.0146 mol HClO₄

Step 5: Calculate the concentration of HClO₄

0.0146 moles of HClO₄ are in 8.99 mL of solution.

[HClO₄] = 0.0146 mol/0.00899 L = 1.62 M

alkaline metals are lithium, sodium, rubidium, potassium, cesium and francium.

alkali metals have electronegativity from 0.7 to 1, lowest in periodic table of elements, which means that alkali metals (i group in periodic table) has positive oxidation number in compounds.

electronegativity is a chemical property that describes the tendency of an atom to attract a shared pair of electrons towards itself.

alkaline metals (far left in main group) have lowest ionizations energy and easy remove valence electrons,

for example, potassium is the alkali metal and has a single valence electron in the outer electron shell.

electron configuration of potassium is: ₁₉k 1s²2s²2p⁶3s²3p⁶4s¹.

they can not exist alone in nature, because they are very reactive.