I think it is full because an atom is really small and can’t really be unreactive
Answer:
ΔHrxn = - 1534.3 J
Explanation:
Given the assumptions and the formula for the change in enthalpy:
ΔHrxn = m x C x ΔT, where
m is the mass of solution given 135.4 g
C is the heat capacity 4.2 J/g .K and,
ΔT is the change in temperature
we have ,
T₁ = ( 18.1 + 273) K = 291.1 K
T₂ = ( 15.4 +273) K = 288.4 K
ΔHrxn = 135.3 g x 4.2 J/gK x ( 288.4 -291.1 ) K = - 1534.3 J
After verifying our result has the correct unit, the answer is -1534.3 Joules, and the negative sign tells us it is an endothermic reaction decreasing the final temperature.
Mass of sodium thiosulfate 
is 110. g
Volume of the solution is 350. mL
Calculating the moles of sodium thiosulfate:
= 0.696 mol
Converting the volume of solution to L:
Finding out the concentration of solution in molarity:
C. a scientific approach to answering questions
