Answer:

Explanation:
Mole ratio


Moles of CO₂

Use formula to find mass

Relative molecular mass of CO₂ = 12 + 16 × 2 = 44


Answer:
He developed the concept of concentric electron energy levels
Explanation:
Before Bohr's model, Rutherford's model was proposed. This model explains most of the properties of the atom but failed to explain the stability of the atom.
As per Rutherford's model, electrons revolve around the nucleus in the orbit.
But revolving electron in their orbit around nucleus would give up energy and so gradually move towards the nucleus and therefore, eventually collapse.
Bohr's proposed that the electrons around the nucleus move orbit of fixed energy called "stationary states". Electrons in these stationary states do not radiate energy.
Therefore, proposal of concentric electron energy levels refine the atomic models.
Answer:
Explanation:
In CF4 and NF3, the valence electron groups on the central C and N atoms have a tetrahedral arrangement. The shapes of the molecules are determined by the number of bonding and nonbonding of electrons: since CF4 has four bonded atom(s) and zero lone pair(s) of electrons, the shape is tetrahedral.
Answer:
Formation. Main-sequence stars, including the sun, form from clouds of dust and gas drawn together by gravity. ... The core that is left behind will be a white dwarf, a husk of a star in which no hydrogen fusion occurs. Smaller stars, such as red dwarfs, don't make it to the red giant state.
Explanation: