Question

Calculate Difference in masses of 10^3 moles each of magnesium atoms and magnesium ions. (Mass of an electron=9.1X10-31kg)
Pls answer fast

Answer 1

We have to find the difference in masses of 10³ moles of each magnesium atoms and magnesium ions.

Solution : we know, a magnesium ion is formed by ejecting of two electrons from its outermost orbit.

I.e., Mg ⇔Mg²⁺ + 2e¯

so, difference in mass of a Magnesium atom to the mass of a magnesium ion = 2 × mass of each electron

So, difference in masses of 10³ moles of each magnesium atoms and magnesium ions = 2 × mass of each electron × 10³ moles × Avogadro's number

= 2 × 9.1 × 10¯³¹ kg × 10³ × 6.022 × 10²³

= 109.6004 × 10¯⁵ kg

= 1.096004 × 10¯³ kg ≈ 1.096004 g

Therefore difference in masses is 1.096004 g (approximately)