Answer:
-154KJ/mol
Explanation:
mole of 100ml sample of 0.2M aqueous HCl = Molarity × volume in Liter
= 0.2 × 100 / 1000 ( 1L = 1000 ml) = 0.02 mol and 0.02 mole of HCl solution require 0.02 mole of ammonia according to the mole ratio in the balanced equation.
Heat loss by the reaction = heat gain by calorimeter = mcΔT + 480 J/K
where m is the mass of water = 100g + 100g = 200g since mass of 100ml of water = 100g and it is in both of them and specific heat capacity of water 4.184 J/gK
heat gain by calorimeter = (4.184 × 200 + 480) × 2.34 = 3081.3 J
ΔH per mole = heat loss / number of mole = 3081.3 / 0.02 = 154065.6 = -154KJ/mol
Answer:
Two elements in same group having similar properties.
Explanation:
The elements shows similar properties if they have same number of valance electrons.
As we move left to right in periodic table the number of valance electrons increases in case of every element
When we move top to down in the group of periodic table the number of valance electrons remain same. So the elements in same group shows similar properties.
For example:
Fluorine and chlorine are present in same group, both have same valance electrons so they shows similar properties.
Electronic configuration of fluorine.
F₉ = [He] 2s² 2p⁵
Electronic configuration of chlorine.
Cl₁₇ = [Ne] 3s² 3p⁵
Both have same number of valance electrons that's why showing similar physical and chemical properties.
By not shaking it up or leaving it in the heat.
Answer:Typical physical properties of metals : high melting points. good conductors of electricity. good conductors of heat.
Explanation:
Answer:
2.19 x 10^-12.
Explanation:-
The relation between Ka and Kb for an acid and it's conjugate base is
Ka x Kb = Kw where Kw = ionic product of water.
So Kb = 10^-14 / (4.57 x 10 ^ -3)
= 2.19 x 10^-12