The atomic number is 8
Atomic number=number of proton or number of electrons
<u>Answer:</u> The average rate of the reaction is 
<u>Explanation:</u>
To calculate the molarity of hydrogen gas generated, we use the equation:

Moles of hydrogen gas = 
Volume of solution = 250 mL = 0.250 L (Conversion factor: 1 L = 1000 mL)
Putting values in above equation, we get:

Average rate of the reaction is defined as the ratio of concentration of hydrogen generated to the time taken.
To calculate the average rate of the reaction, we use the equation:

We are given:
Concentration of hydrogen generated = 0.1564 M
Time taken = 20.0 minutes
Putting values in above equation, we get:

Hence, the average rate of the reaction is 
The number of lone pairs that are most likely found on the central atom is zero. There are no lone pairs found on the central atom.
Answer:
46
Explanation:
Sodium metal has a molar mass of
22.99
Answer:
number three is the answer moderate