Answer:
difference between metal and alloy is that the metal is a pure substance whereas the alloy is a mixture of two or more components.
Explanation:
Mostly the metalloids have the appearance just like the metallic appearance And also they are the brittle one's . Boron and silicon are the example. Note; By combining with other metals metalloid can form the alloy
<span>As we know that
1 cu cm H2O = 1 mL H2O = 1g H2O
now
Heat of fusion of water = 79.8 cal/g
and
Heat of vaporization of water = 540 cal/g
Atomic weight of water : H=1 O=16 H2O=18
now by calculating and putting values
65.5gH2O x 79.8cal/gH2O x 1gH2O/540cal = 9.68g H2O (steam)
9.68gH2O x 1molH2O/18gH2O x 22.4LH2O/1molH2O = 12.0 L H2O
hope it helps</span>
Answer:
constant
Explanation:
A constant is a number with a fixed value in a specific mathematical context
Answer is: ph value is 3.56.
Chemical reaction 1: H₂CO₃(aq) ⇄ HCO₃⁻(aq) + H⁺(aq); Ka₁ = 4,3·10⁻⁷.
Chemical reaction 2: HCO₃⁻(aq) ⇄ CO₃²⁻(aq) + H⁺(aq); Ka₂ = 5,6·10⁻¹¹.
c(H₂CO₃) = 0,18 M.
[HCO₃⁻] = [H⁺<span>] = x.
</span>[H₂CO₃] = 0,18 M - x.
Ka₁ = [HCO₃⁻] · [H⁺] / [H₂CO₃].
4,3·10⁻⁷ = x² / (0,18 M -x).
Solve quadratic equation: x = [H⁺] =0,000293 M.
pH = -log[H⁺] = -log(0,000293 M).
pH = 3,56; second Ka do not contributes pH value a lot.
