The formula for K+ and S-2 is K2S because you need 2 potassium ions to balance out the sulfide ion
Answer: All changes of state involve the transfer or energy
Explanation: i got my information from this site
https://www.esrl.noaa.gov/gmd/education/info_activities/pdfs/CTA_the_water_cycle.pdf
The anode is the electrode where the oxidation occurs.
Cathode is the electrode where the reducction occurs.
Equations:
Mn(2+) + 2e- ---> Mn(s) Eo = - 1.18 V
2Fe(3+) + 2e- ----> 2 Fe(2+) 2Eo = + 1.54 V
The electrons flow from the electrode with the lower Eo to the electrode with the higher Eo yielding to a positive voltage.
Eo = 1.54 V - (- 1.18) = 1.54 + 1.18 = 2.72
Answer: 2.72 V
Covalent bond , hopefully this help :) explanation : .....
Balancing of chemical equation is essential because of the law of conservation of mass, which states that the mass of a system can not be created or removed.
The second equation is balanced
This is because the number of elements of each atom in the product side equal the number of elements of each atom on the reactant side.
The first equation is not balanced

This is because there is 1 molecule of
on reactant side as compared to 3 molecules of 
To balance the equation we add a coefficient of 3 on sulphuric acid (
) and a coefficient of 3 on hydrogen (
)
