There are 3 sig figs. 8 and 2 are obvious. The ending 0 is significant because it is at the end of a decimal number, and doesn't have to be measured.
The correct answer is + 32.5 J because heat is absorbed here by copper not evolved also after calculation we will find the H value is positive, lets calculate it:
H = m C Δt where:
m = 10 g
C = 0.13 J/g.°C
Δ t = final temperature - initial temperature = 50 - 25 = + 25 °C
so H = 10 x 0.13 x (+25) = + 32.5 J
Answer: Fluorine contains seven valence electrons. It needs one more electron to complete its octet. The oxidation number is 1- and indicates fluorine will gain or share one electron when it combines with another atom to become a more stable compound.
Explanation: Fluorine contains seven valence electrons. It needs one more electron to complete its octet. The oxidation number is 1- and indicates fluorine will gain or share one electron when it combines with another atom to become a more stable compound.
Answer:
if you mix any halogen with any alkali then ionic salt will be formed and also this will cause an exothermic reaction in which heat is getting released
Decrease temperature and decrease of concentration will decrease reaction rate, because less molecules will be able to react.
