The answer is the mass number! (:
Answer:
M = 16.8 M
Explanation:
<u>Data:</u> HNO3
moles = 12.6 moles
solution volume = 0.75 L
Molarity is represented by the letter M and is defined as the amount of solute expressed in moles per liter of solution.

The data is replaced in the given equation:

-20.16 KJ of heat are released by the reaction of 25.0 g of Na2O2.
Explanation:
Given:
mass of Na2O2 = 25 grams
atomic mass of Na2O2 = 78 gram/mole
number of mole = 
= 
=0. 32 moles
The balanced equation for the reaction:
2 Na2O2(s) + 2 H2O(l) → 4 NaOH(aq) + O2(g) ∆Hο = −126 kJ
It can be seen that 126 KJ of energy is released when 2 moles of Na2O2 undergoes reaction.
similarly 0.3 moles of Na2O2 on reaction would give:
= 
x = 
= -20.16 KJ
Thus, - 20.16 KJ of energy will be released.
Answer:

Explanation:
Hello,
In this case, by knowing that 1 inch equals 2.54 cm and 60 seconds equals 1 min, the resulting value results:

Best regards.
Thomson's model included Protons and Electrons. His model is referred to as 'Plum Pudding' because of it.