Answer:
b it has different kinds of atoms
Answer:
The concentration is 0,2925M
Explanation:
We use the formula
C initial x V initial = C final x V final
11,7 M x 25 ml = C final x 1000 ml
C final= (11,7 M x 25 ml)/1000 ml = 0, 2925 M
(This formula applies to liquid solutions)
Answer:
0.804g of NaHCO₃ you must add
Explanation:
pKa of HCO₃⁻/CO₃²⁻ is 10.32.
It is possible to find pH of a buffer by using H-H equation, thus:
pH = pka + log [A⁻] / [HA]
<em>Where [HA] is concentration of acid (HCO₃⁻) and [A⁻] is concentration of conjugate acid (CO₃²⁻).</em>
Moles of CO₃²⁻ = K₂CO₃ are:
4.00g ₓ (1mol / 138.206g) = 0.0289 moles CO₃²⁻
Replacing:
10.80 = 10.32 + log [0.0289] / [HCO₃⁻]
[HCO₃⁻] = 0.009570 moles you need to add to obtain the desire pH
As molar mass of NaHCO₃ is 84.007g/mol, mass of NaHCO₃ is:
0.009570 moles ₓ (84.007g / mol) =
<h3>0.804g of NaHCO₃ you must add</h3>
Answer:
Diamond, graphite and fullerness
Explanation:
Diamond is clear and transparent but graphite is black and opaque
