Answer:
Sofia the firstttdbshsgshaksus
Answer:
Ea=5.5 Kcal/mole
Explanation:
Let rate constant are
and
at temperature
and 
By using Arrhenius equation at two different two different temperature,
By putting value of R=2 cal/mole.K

By rounding off upto 2 significant figure;

Answer:
sodium sulphide.
Explanation:
First, let us obtain the percentage of sulphur in both compounds. This is illustrated below:
For sodium sulphide(Na₂S):
Molar Mass of Na₂S = (23x2) + 32 = 46 + 32 = 78g/mol
Percentage of sulphur in Na₂S is given by:
32/78 x 100 = 41%
For zinc sulphide(ZnS):
Molar Mass of ZnS = 65.4 + 32 = 97.4g/mol
Percentage of sulphur in ZnS is given by:
32/97.4 x 100 = 33%
From the results obtained sulphur has the highest percentage by mass in sodium sulphide.
Dwarfs - A
Giants - C
Main Sequence Stars - B
Supergiants - D