Answer: The beaker will not tip over when placed on the hot plate
Justification:
Since beakers have flat surface bottoms (usually and this is the condition to use them for this particular application) they can be placed safely on the hot plate without the risk that the they tip over.
Beakers are wide mouth cylindrical vessels used in laboratories to store, mix and heat liquids. Most are made of glass, in which case the glass is resistant to the flame and does not break when exposed to high temperatures or when is heated by direct contact on a hot plate.
So, their safe shape (flat bottom) that makes them stable, along with their ability to withstand high temperatures, make them suitable to heat solutions in laboratories.
Cobalt because it has an atomic mass of 58 and 33 neutrons.
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;
