Answer:
A meter is 100 times larger then a centimeter
-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.
There is 6 non - bonding pairs.
Let me show you one easy method to do this.
o22-, oxygen valence electron = 6 here we have two so total 12, and -2 that means we add electrons so it’s all equal to 14 right.
whenever need to find lone pair, subtract the number you get with the lowest multiple of 8.
here we total 14 valence electron right so lowest multiple of 8 would be 8.
so 14 - 8 = 6 and that is our answer.
Let me know if you have Problem with chemistry.
Answer:
0.675 atm
513 Torr
Explanation:
Given is that, the atmospheric pressure on the surface of Venus is
6.84 X 10⁴ Pa.
1 atm (atmospheric pressure) is equal to 101325 pascal (Pa).
To convert divide the pressure value by 101325.
Pressure in atm = 
= 0.675055 atm
Rounding it off to 3 significant digits: 0.675 atm
Now, one Torr is 133.322 Pa. For conversion, divide the pressure value by 133.322.
Pressure in Torr = 
=513.04219 Torr
Rounding it off to 3 significant digits: 513 Torr