How many atoms of o are in 2.12 miles of no3

38.3×10²³ atoms of oxygen

Explanation:

Given data:

Moles of NO₃ = 2.12 mol

Atoms of oxygen = ?

Solution:

One mole of any substance contain 6.022 × 10²³ atoms.

The number 6.022 × 10²³ is called Avogadro number.

It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.

One mole of NO₃ = 6.022 × 10²³ atoms

one molecule of NO₃ contain three atoms of oxygen thus in 2.12 moles number of oxygen atoms are:

2.12×3× 6.022 × 10²³ atoms = 38.3×10²³ atoms of oxygen

"you start with 15.67 g mgco3-xh2o, when heated and all the water is removed, you are left with 7.58 g mgco3 only.

therefore, you had 15.67 - 7.58 = 8.09g h2o  

moles of each :

7.58g mgco3 = ? moles = 7.58g / 83.4g/mole = 0.09moles  

8 09g h2o = ? moles = 8.09g / 18g/mole = 0.44moles  

molar ratio between the two by dividing both numbers by the smallest number :

0.09 / 0.09 = 1  

0.44 / 0.09 = 4.8  

mgco3-5h2o"