Question

1. na2cro4 # of molecules: 1 # of elements: 3 name of element: na= cr= o= # of atoms: 1 2 6 total # of atoms: 9 the #4 is a subscript (coefficient or subscript)

Explanation:

Step1: Identify elements in formula

The formula $\text{Na}_2\text{CrO}_4$ has 3 elements: sodium (Na), chromium (Cr), and oxygen (O).

Step2: Count atoms of each element

• Sodium (Na): The sub - script 2 indicates 2 Na atoms.
• Chromium (Cr): There is 1 Cr atom (no sub - script means 1).
• Oxygen (O): The sub - script 4 indicates 4 O atoms.

Step3: Calculate total number of atoms

$2$ (Na) + $1$ (Cr)+$4$ (O)=$7$ atoms.

Answer:

of molecules: 1

of elements: 3

Name of element: Na, Cr, O

of atoms: Na = 2, Cr = 1, O = 4

Total # of atoms: 7
The #4 is a subscript