-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.
Methanol is the substance that can be broken down by chemical means, the remaining ones are elements.
K gives 1 electron, and Br takes 1 electron.
Answer:
Explanation:
C = 41.4/12 = 3.43
H = 3.47/1 = 3.47
O = 55.1/16 =3.44
CHO is the skeletal formula (divide each by the lowest number above). The results are close enough to 1 to be 1.
(CHO)_x = 116
C + H + O = 29
(29) _ x = 116
x = 116/29
x = 4
So there area 4 carbons 4 hydrogens and 4 oxygens.
The correct formula is C4H4O4