Answer:
A
Explanation:
You want one whole number to the left of the decimal. Depending on how many times u have to move the decimal over (in this case 7 times) determines the number you put after 10. And its -7 because to get it back to its original position you have to move left, which is a negative direction.
Mass of X₄Z₅= 378.621 g
<h3>Further explanation</h3>
Given
3.89 x 10²³ molecules/formula units of X₄Z₅
Required
Mass of X₄Z₅
Solution
1 mol = 6.022 x 10²³ particles(molecules, atoms, ions)
N = n x No
No = Avogadro's number
n = mol
Conversion to mol :
n = N : No
n = 3.89 x 10²³ : 6.022 x 10²³
n = 0.646
MW X₄Z₅ :
= 4 x 76.15 + 5 x 56.3
= 304.6 + 281.5
= 586.1 g/mol
Mass :
= mol x MW
= 0.646 x 586.1
= 378.621 g
Answer:
answer........of the question
Surface tension :<span>the tension of the surface film of a liquid caused by the attraction of the particles in the surface layer by the bulk of the liquid, which tends to minimize surface area.</span>