Answer: Pigment.
Explanation: Our hair color is determined by two types of pigment, Eumelanins, and Pheomelanins. Which together produces all the natural hair colors we see every day with other people.
We need to first find the molarity of Ba(OH₂) solution.
A mass of 3.24 mg is dissolved in 1 L solution.
Ba(OH)₂ moles dissolved - 3.24 x 10⁻³ g/171.3 g/mol = 1.90 x 10⁻⁵ mol
dissociaton of Ba(OH)₂ is as follows;
Ba(OH)₂ --> Ba²⁺ + 2OH⁻
1 mol of Ba(OH)₂ dissociates to form 2OH⁻ ions.
Therefore [OH⁻] = (1.90 x 10⁻⁵)x2 = 3.8 x 10⁻⁵ M
pOH = -log[OH⁻]
pOH = -log (3.8 x 10⁻⁵)
pOH = 4.42
pH + pOH = 14
therefore pH = 14 - 4.42
pH = 9.58
Answer:
60%
Explanation:
M(NH4NO3) = 2*14 +4*1 +3*16 = 80 g/mol
M(3O) = 3*16 = 48 g/mol
(48/80) *100 % =60% oxygen by mass.
Because the amount of hydrogens all depends on the valence electrons
By use of ideal gas equation PV= nRT where n is the number of moles,P = pressure, V = volume, R= gas constant (0.08206 L. atm/ mol.k) ant T is the temperature,
to calculate the number of moles(n) =PV/RT
convert ml to L, that is 200/1000= 0.2 L
convert mmHg to atm, that is 780mm hg x 1atm/ 760 mm hg= 1.026 atm
convert temperature to kelvin, that is 135 +273= 408 k
n is therefore= (0.2 x 1.026)/ ( 0.08206 x 408)= 6.129 x10^-3 moles
from avogadro constant 1moles = 6.02 x10^23 molecules what about 6 .129 x10^-3 moles
= ( 6.02 x10^23) x (6.129 x10^-3)/ 1mole = 3.69 x10^21 molecules