HCl:
<span>
m=48,2g
M=36,5g/mol
n = m/M = 48,2g / 36,5g/mol = 1,32mol
1mol : 4mol
MnO</span>₂ + 4HCl ⇒ MnCl₂ + Cl₂ + 2H₂O
0,86mol : 1,32mol
limiting reagent
0,33 will react
HCl is limiting reagent.
-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.
Igneous rocks from cooling magma<span>. </span>Granite<span> is an igneous rock </span>formed<span> from </span>magma<span>that </span>cooled slowly<span> underground. As the </span>magma slowly cools<span>, large mineral crystals form.
</span>
'cause many alpha-particle goes without any deflection........
B) energy is absorbed by the reaction
is right answer.