The Chemical fomulla for Zinc Phosphate
Zn3(PO4)2
The average atomic mass of Boron: 10.431 amu
<h3>Further explanation
</h3>
Isotopes are atoms whose no-atom has the same number of protons while still having a different number of neutrons.
So Isotopes are elements that have the same Atomic Number (Proton)
Atomic mass is the average atomic mass of all its isotopes
In determining the mass of an atom, as a standard is the mass of 1 carbon-12 atom whose mass is 12 amu
Mass atom X = mass isotope 1 . % + mass isotope 2.% + ...
The average atomic mass of boron :

The ph of the best buffer is 4.74
The given acetic acid is a weak acid
The equation of the pH of the buffer
pH = pKa + log ( conjugate base / weak acid ).
For best buffer the concentration of the weak acid and its conjugate base is equal.
pH = pKa + log 1
pH = pKa + 0
pH = pKa
given Ka = 1.8 × 10⁻⁵
pKa = - log ka
pH = -log ( 1.8 × 10⁻⁵ )
pH = 4. 74
Hence the pH of the best buffer is 4.74
Learn more about the pH on
brainly.com/question/22390063
#SPJ4
The molarity of Sr(OH)2 solution is = 0.1159 M
calculation
write the equation for reaction
that is, Sr(OH)2 +2HCl→ SrCl2 + 2 H2O
then finds the mole of HCl used
moles = molarity x volume
=40.03 x0.1159 = 4.639 moles
by use of mole ratio between Sr(OH)2 to HCL which is 1 :2 the moles of Sr(OH)2 is therefore = 4.639 x1/2 = 2.312 moles
molarity of Sr(OH)2 is = moles / volume
=2.312 /20 =0.1159 M
d = √((x1 - x2)2 + (y1 - y2)2)
( -2 , 5 ) ( 12 , -1 )
↑ ↑ ↑ ↑
x1 y1 x2 y2
d = √((-2 - 12)2 + (5 - (-1))2) = √((-14)2 + 62) = √(196 + 36) = √232 = 2√58 ≈ 15.23