Seismic waves hope this helps.
Answer:
The Earth's surface is constantly changing through forces in nature. The daily processes of precipitation, wind and land movement result in changes to landforms over a long period of time. Driving forces include erosion, volcanoes and earthquakes. People also contribute to changes in the appearance of land.
The SI unit for amount<span> of </span>substance<span> is the </span>mole<span>. It has the unit symbol mol. The proportionality constant is the inverse of the Avogadro constant. The </span>mole<span> is defined as the </span>amount<span> of </span>substance that contains<span> an equal </span>number<span> of elementary entities as there are </span>atoms in 12g<span> of the </span>isotope<span> carbon-</span>12<span>.
Hope This Helped! :3</span>
Answer:
a. 7.8*10¹⁴ He⁺⁺ nuclei/s
b. 4000s
c. 7.7*10⁸s
Explanation:
I = 0.250mA = 2.5 * 10⁻³A
Q = 1.0C
1 e- contains 1.60 * 10⁻¹⁹C
But He⁺⁺ Carrie's 2 charge = 2 * 1.60*10⁻¹⁹C = 3.20*10⁻¹⁹C
(A).
No. Of charge per second = current passing through / charge
1 He⁺⁺ = 2.50 * 10⁻⁴ / 3.2*10⁻¹⁹C
1 He⁺⁺ = 7.8 * 10¹⁴ He⁺⁺ nuclei
(B).
I = Q / t
From this equation, we can determine the time it takes to transfer 1.0C
I = 1.0 / 2.5*10⁻⁴ = 4000s
(C).
Time it takes for 1 mol of He⁺⁺ to strike the target =?
Using Avogadro's ratio,
1.0 mole of He = (6.02 * 10²³ ions/mol ) * (1 / 7.81*10¹⁴ He ions)
Note : ions cancel out leaving the value of the answer in mols.
1.0 mol of He = 7.7 * 10⁸s
