We know that
1) empirical formula of a compound is the representation of a molecules with the elements in simplest mole ratio.
2) the molar mass is the actual proportion of moles of elements present in a molecule
3) there is a simple ratio between the molar mass and empirical mass a molecule
Now let us solve each problem
1) empirical formula of 
will be 
2) empirical formula of 
will be
3) empirical formula of 
will be 
4) the molecular formula will be :
the molecular formula = 4 X empirical formula = 4 X CO = 
5) the mole ratio of Cl and Cr is 
empirical formula will be 
Chemistry affects all aspects of life and most natural events because all living and nonliving things are made of matter.
Answer:
C) Krypton is a noble gas, so it was difficult for chemists to find it, as though it was a secret.
Explanation:
Mass of carbon monoxide : 0.95 g
<h3>Further explanation</h3>
A reaction coefficient is a number in the chemical formula of a substance involved in the reaction equation. The reaction coefficient is useful for equalizing reagents and products.
Reaction
Fe₂O₃(s) + 3CO(g) → 2Fe(s) + 3CO₂
MW Fe₂O₃ : 159,69 g/mol
mol Fe₂O₃ :
mol ratio Fe₂O₃ : CO = 1 : 3, so mol CO :
mass CO (MW = 28,01 g/mol) :
