Ba2+ and Cu2+, and Sr2+ and Li+
The postulate of Dalton's atomic theory which is a result of the law of conservation of mass is: Atoms are indivisible particles, which can neither be created nor destroyed in a chemical reaction.
Answer:
in a chemical reaction of NaOH with H2O, after NaOH is completely disassociated, we will find Na+ and OH- ions in the solution. (option C).
Explanation:
In a reaction where NaOH is added to H2O.
NaOH is considered a strong base, this means that in an aqueous solution ( in water) it's able to completely disassociate in ions.
There will not remain any NaOH in the solution. This means option D is not correct.
The ions in which NaOH will disassociate are : NaOH → Na+ + OH-
These ions we will find in the solution.
Not only Na+ because NaOH is a strong base, so there will be a lot of OH- ions as well in solution.
This means in a chemical reaction of NaOH with H2O, after NaOH is completely disassociated, we will find Na+ and OH- ions in the solution.
Answer: 3.01 x 10^24 atoms
Explanation:
Based on Avogadro's law:
1 mole of any substance has 6.02 x 10^23 atoms
So, 1 mole of SI = 6.02 x 10^23 atoms
5.0 moles = Z atoms
To get the value of Z, cross multiply:
(Z atoms x 1 mole) = (6.02 x 10^23 atoms x 5.0 moles)
Z atoms•1 mole = 30.1 x 10^23 atoms•moles
Divide both sides by 1 mole
Z atoms•1 mole / 1 mole = 30.1 x 10^23 atoms•moles / 1 mole
Z = 30.1 x 10^23 atoms
[Place Z in standard form
So, Z = 3.01 x 10^24 atoms]
Thus, there are 3.01 x 10^24 atoms in 5.0 moles in SI
