Density= mass/volume aluminum can= 174 •g/ 4 • cm ^3. =2.76•g•cm ^-3
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 
Answer:
D
Explanation:
It occurs when the outermost electrons are permanently transferred to another atom.
N is as electronegative as Cl is. So Cl doesnt react with O, N
Answer:
A
Explanation: The real molecule is too small so had to build a model to make it viewable