Answer:
0.550
Explanation:
The absorbance (A) of a substance depends on its concentration (c) according to Beer-Lambert law.
A = ε . <em>l</em> . c
where,
ε: absorptivity of the species
<em>l</em>: optical path length
A 45 mM phosphate solution (solution A) had an absorbance of 1.012.
A = ε . <em>l</em> . c
1.012 = ε . <em>l</em> . 45 mM
ε . <em>l</em> = 0.022 mM⁻¹
We can find the concentration of the second solution using the dilution rule.
C₁ . V₁ = C₂ . V₂
45mM . 11mL = C₂ . 20.0 mL
C₂ = 25 mM
The absorbance of the second solution is:
A = (ε . <em>l</em> ). c
A = (0.022 mM⁻¹) . 25 mM = 0.55 (rounding off to 3 significant figures = 0.550)
Use Avogadro's number which is numerically equal to ...
( 6.02 multiply by 10 to the power of negative 23)
Avocado's number is the number of particle(molecules, ions, atoms) present in one mole of substance.
number of molecule in 0.809 mole of h20 = ....
one mole of h20 contains (6.02* 10^-23)
0.809 mole contains....(6.02* 10^-23) (0.809)
which is equal to [4.951* 10 ^-23]
if I made no mistake in calculation...it must be correct
Answer:
Hey there!
That would be the alkaline earth metals.
Hope this helps :)
Ratio of neutrons & protons .
