1- Molar solutions: based on number of moles of chemical in 1 litre of solution
2- Weight % solution: the weight of chemical divided by the total weight of the solution (chemical + water) and multiplied by 100.
I believe you mean what amount of O2 contains 1.8 x 10^22 molecules.
Solution: Divide your number of molecules by the number of molecules in one mole (6.02 x l0^23)
02989 moles. Rounded to the nearest hundredths,.<span>0299</span>
4.3 x 10⁻⁸dm⁻²
Explanation:
Problem:

To solve this problem, we have apply the right rule of indices operation.
If we have an indices in the form;
= (
)
Solving this problem:
=
x 10
)
= 0.43 x 10⁻⁷
= 4.3 x 10⁻¹ x 10⁻⁷
= 4.3 x 10⁻⁸
for the units:
= 
The solution is: 4.3 x 10⁻⁸dm⁻²
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long division brainly.com/question/1747117
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