Answer:
There are 10.0 moles of beryllium oxide in a 250 grams sample of the compound.
Explanation:
We can calculate the number of moles (η) of BeO as follows:

Where:
m: is the mass = 250 g
M: is the molar mass = 25.0116 g/mol
Hence, the number of moles is:

Therefore, there are 10.0 moles of beryllium oxide in a 250 grams sample of the compound.
I hope it helps you!
You always adjust numbers and it will be before the element
so you Neva add or change a subscript
Answer:
una ma parra quen est a qui 23^5(-8)
Explanation:
Denser objects and substances experience a greater gravitational force acting upon their mass. This is why materials of different densities form layers. ... It is less dense than the Earth's crust, which is a solid. This is why the Earth's surface and atmosphere form distinct layers.
pls give brainliest if this helped :)