1- One mole is = 6.02 x 10^23 of anything, So one mole of atoms is 6.02x10^23.
2- when the balloon contains 0.15 moles of Co2 gas so:
the no.of molecules of Co2 = 0.15 x 6.02x 10^23
= 9.0 x 10^22
Answer:
The ground state electron configuration of ground state gaseous neutral tellurium is [Kr]. 4d10.
Answer: D=8.27 g/cm³
Explanation:
Density is mass/volume. Mass is in grams and volume is in liters. In this case, the problem wants our volume to be in cm³. All we need to do is to make some conversions to convert kg/m³ to g/cm³.

With this equation, the m³ and kg cancel out, and we are left with g/cm³.
D=8.27 g/cm³