The total weight of both objects : 7.035 x 10⁻⁸ kg
<h3>Further explanation</h3>
Given
The weight of a grain of sand : 3.5 x 10⁻¹⁰ kg
The weight of one hair from his eyebrow : 7 x 10⁻⁸ kg
Required
The total weight of both objects
Solution
Scientific Notation consists of 2 parts
1. the first part: the first digit followed by the decimal point
2. The second part: the power of 10 (the exponents).which shows the number of digits after the decimal point
To add/subtract, the exponents must be the same and then add/subtract the coefficient
- convert the largest exponent (7 x 10⁻⁸)
7 x 10⁻⁸ = 700 x 10⁻¹⁰

Answer:
760 mm of Hg
Explanation:
If the gases A , B and C are non reacting , then according to <u>Dalton's </u><u>Law </u><u>of</u><u> </u><u>Partial </u><u>Pressure</u> the total pressure exerted is equal to sum of individual partial pressure of the gases .
If there are n , number of gases then ,
Here ,
- Partial pressure of Gas A = 400mm of Hg
- Partial pressure of Gas B = 220 mm of Hg
- Partial pressure of Gas C = 140mm of Hg
Hence the total pressure exerted is ,
Substitute ,

Add ,

<u>Hence</u><u> the</u><u> </u><u>total</u><u> pressure</u><u> exerted</u><u> by</u><u> the</u><u> </u><u>gases </u><u>is </u><u>7</u><u>6</u><u>0</u><u> </u><u>mm </u><u>of </u><u>Hg</u><u>.</u>
<em>I </em><em>hope</em><em> this</em><em> helps</em><em>.</em>
(2.03x10^22)/(6.02x10^23) = .033721 mol Li
I hope this helps, if not, i am sorry
The particles are atoms, his theory is the atomic theory