MH₂ = 2×mH = 2×1g = 2 g/mol
Answer:
The correct answer to the question is
The standard heat of reaction for the reaction is
a. 216.8 kJ released per mole
Explanation:
The heat of reaction is given by [Heat of formation of products] - [Heat of formation of reactants]
In the question we have, heat of formation of the products Zn+2 (aq) = -152.4 kJ/mole and the heat of formation of the reactants = 64.4 kJ/mole
Therefore, the heat of formation of the reaction = (-152-64.4) kJ/mole or
-216.8 kJ/mole released
Answer:
Dissolves a chemical sample well at high temperatures.
Does not dissolve a chemical sample well at low temperatures.
Explanation:
Recrystallization involves the dissolution of the solute in a solvent at high temperature. As the solution cools, it becomes saturated and the solute crystallizes out of the solution.
A good recrystallization solvent must only dissolve the solute at high temperature and must not dissolve it at low temperature. Hence, these are the two conditions required for any good recrystallization solvent.
Answer:
0.29 moles of PbCl₂
Explanation:
Given data:
Mass of lithium chloride = 24.3 g
Moles of PbCl₂ = ?
Solution:
Chemical equation;
PbSO₄ + 2LiCl → PbCl₂ + Li₂SO₄
Number of moles of LiCl:
Number of moles = mass/ molar mass
Number of moles = 24.3 g/ 42.394 g/mol
Number of moles = 0.57 mol
Now we will compare the moles of PbCl₂ with LiCl .
LiCl : PbCl₂
2 : 1
0.57 : 1/2×0.57 = 0.29 mol
LEAD is the element that has this electron configuration