Answer:
Total mass of leaked fluorine in six months= 0.405 kg
Explanation:
From the given,
Leaked mass of freon = 35.12 gm
Molecular mass of freon = 
Total weeks per month = 4
Fluorine released into the air in total weeks = 
3 molecules of fluorine is present in the freon


Total mass of fluorine leaked in six months = 
The answer is helium 0.09 kg/m³.
The wave will move faster in the gas that is having lowest density.
As comparison to other gases-hydrogen, oxygen and radon; helium has the lowest density that is 0.09 kg/m³.
So, waves will move fastest in helium gas as it is having lowest density.
So the answer is helium gas that is waves will move fastest in helium gas.
Answer:
in the presence of water H2O
Na2CO3 (S) --> 2Na+ (aq)+ (CO3)2-(aq)
One mole of sodium carbonate produces two moles of Na+ ions
Therefore 0.207 moles produces 0.414 moles of Na+ ions
= 0.414 moles of Na+ ions
Explanation:
In water
Na2CO3 --> 2Na+ (aq)+ (CO3)2-(aq)
In a limited reaction, the carbonate ion reacts with the water molecules as follows
(CO3)2-(aq) + H2O←→HCO3-(aq) + OH-(aq)
sodium carbonate or soda ash dissolves in water to give 2 sodium cations and one carbonate anion
Answer:
208.7°C was the initial temperature of the limestone.
Explanation:
Heat lost by limestone will be equal to heat gained by the water

Mass of limestone = 
Specific heat capacity of limestone = 
Initial temperature of the limestone = 
Final temperature =
=T = 51.9°C

Mass of water= 
Specific heat capacity of water= 
Initial temperature of the water = 
Final temperature of water =
=T = 51.9°C



On substituting all values:


208.7°C was the initial temperature of the limestone.