Answer:
ΔH°r = -483.64 kJ
Explanation:
Let's consider the following balanced equation.
2 H₂(g) + O₂(g) ⇒ 2 H₂O(g)
We can calculate the standard enthalpy change of the reaction (ΔH°r) using the following expression.
ΔH°r = ∑ΔH°f(p) × np - ∑ΔH°f(r) × nr
where
ΔH°f: standard heat of formation
n: moles
p: products
r: reactants
ΔH°r = ΔH°f(H₂O(g)) × 2 mol - ΔH°f(H₂(g)) × 2 mol - ΔH°f(O₂(g)) × 1 mol
ΔH°r = (-241.82 kJ/mol) × 2 mol - 0 kJ/mol × 2 mol - 0 kJ/mol × 1 mol
ΔH°r = -483.64 kJ
the mass of ice taken = 10 g
the mass of water = 250 g
initial temperature of water = 20 C
the final temperature of water = 16. 8 C
specific heat of water = 4.18 J/g*K
the heat absorbed by ice to melt = heat loss by water
heat loss by water = mass X specific heat of water X change in temperature
heat loss by water = 250 X 4.18 X (20-16.8) = 3344 Joules
heat gained by ice = 3344 J
heat gained by ice = enthalpy of fusion X moles of ice
moles of ice = mass / molar mass = 10 / 18 = 0.56 moles
enthalpy of fusion = 3344 / 0.56 = 5971.43 J / mole
Answer:
it gains energy in a quantized amount
Explanation:
when we describe the energy of a particle as a quantized ,we mean that only certain values of energy are allowed....it can only gain the exact amount of energy needed to reach one of the higher energy levels
hope this helps :)
Aww man, I love these types of problems!!!
So, it's a simple formula:
P1*V1/T1=P2*V2/T2
In this case, we remove V(volume) as there is none listed, leaving this:
P1/T1=P2=T2
Think you got it from here? All you gotta do is plug in the numbers and solve
If you have any further problems, just let me know!!
Answer:
atomic number
Explanation:
mass is determined by the protons and neutrons
