Answer:
The only PH range which is not covered by any of the given components of the universal indicator is 7.6-8.0
Hence the PH range 7.6-8 can't be described using universal indicator.
Answer:
24.87× 10²³ atoms of Ni
Explanation:
Given data:
Number of atoms of Ni= ?
Number of moles of Ni = 4.13 mol
Solution:
we will calculate the number of atoms of Ni by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
1 mole = 6.022 × 10²³ atoms
4.13 mol × 6.022 × 10²³ atoms /1 mol
24.87× 10²³ atoms of Ni
When dealing with making diluted solutions from concentrated solutions, we can use the following formula
c1v1 = c2v2
where c1 and v1 are the concentration and volume of the concentrated solution respectively.
c2 and v2 are the concentration and volume of the diluted solution respectively
substituting these values in the above formula,
20 mL x 0.200 M = C x 250.0 mL
C = 0.0160 M