Answer:
Potassium (K) = (2,8,8,1)
This is the element that has three(3) filled energy level and one valence electron
Answer: The oxidation number of Cu decreased
Explanation: In Cu2O equation Cu has an oxidation number of
Cu+1 O-2
then in the product side Cu is represented as a single element.
The rule on oxidation number for an individual element is always O
So Cu has 0 oxidation number.
The number of joules released when 0.64g of steam are cooled from 125 c to 105 c is -26.112 joules
calculation
by use of Q=MCΔ T formula calculate the joules released where
Q( heat) =?
M (mass) = 0.64 g
C (specific heat capacity = 2.04 j/g/c
ΔT(change in temperature) = 105-125 =-20c
Q is therefore = 0.64 g x2.04 j/g/c x -20 c = -26.112 joules
it is okay to have negative value since the reaction is exothermic that is heat is released
