Silicon and gold, both are elements on the periodic table. the rest are alloids or compounds.
The molar mass of the gas : 18 x 10⁻³ kg/mol
<h3>Further explanation</h3>
Given
An unknown gas has one third the root mean square speed of H2 at 300 K
Required
the molar mass of the gas
Solution
Average velocities of gases can be expressed as root-mean-square (V rms)

T = temperature, Mm = molar mass of the gas particles , kg/mol
R = gas constant 8,314 J / mol K
v rms An unknown gas = 1/3 v rms H₂
v rms H₂ :

V rms of unknown gas =


Answer:
Hi! Think of it like this:
You and your family are going to go on a vaction for the holidays, to south america or somewhere else. You´re near the equator so it will be warm. If you were to move there, you might pull out the swimsiutes because most of the time, its useally warm and sunny. They dont really get cold weather. They will have a nice and warm christmas.
The fraction of Earth's radius (6371 km) relative to the thickness of the oceanic (7.5 km) and continental crust (35 km) is 0.12 and 0.55, respectively.
What we know:
- The average radius of Earth (E) = 6371 km
- The average thickness of oceanic crust (O) = 7.5 km
- The average thickness of continental crust (C) = 35 km
We need to convert all the above units from kilometers to miles:

Now, we can calculate the fraction of Earth's radius relative to each type of crust, with the given equation:

- <u>For the oceanic crust (O)</u>:

- <u>For the continental crust (C)</u>:

Therefore, the fraction of Earth's radius relative to the oceanic and continental crust is 0.12 and 0.55, respectively.
You can see another example of calculation of fractions of Earth's radius here: brainly.com/question/4675868?referrer=searchResults
I hope it helps you!
Answer:
South American
Explanation:
When you look at a map of plates, only South American forms a boundary with the African plate out of those specific plates