Stable isotopes are not radioactive nor dangerous.
Unstable isostopes are radioactive and have different mass of the element.
Answer:
The mass of water
= 39.18 gm
Explanation:
Mass of iron
= 32.5 gm
Initial temperature of iron
= 22.4°c = 295.4 K
Specific heat of iron
= 0.448 
Mass of water =
Specific heat of water 
Initial temperature of water
= 336 K
Final temperature after equilibrium
= 59.7°c = 332.7 K
When iron rod is submerged into water then
Heat lost by water = Heat gain by iron rod
(
-
) =
(
-
)
Put all the values in above formula we get
× 4.2 × ( 336 - 332.7 ) = 32.5 × 0.448 × ( 332.7 - 295.4 )
= 39.18 gm
Therefore the mass of water
= 39.18 gm
Equilibrium chemical reaction between chair and boat forms is:
Kc =
![\frac{[Boat form]}{[Chair form]}](https://tex.z-dn.net/?f=%20%5Cfrac%7B%5BBoat%20form%5D%7D%7B%5BChair%20form%5D%7D%20)
Suppose the total number of molecules is x
Number of molecules of chair form is 6.42/100 x
Number of molecules of boat form is 93.58/100 x
Kc =

= 14.6
Answer:
An acid is a substance that donates protons (in the Brønsted-Lowry definition) or accepts a pair of valence electrons to form a bond (in the Lewis definition). A base is a substance that can accept protons or donate a pair of valence electrons to form a bond. Bases can be thought of as the chemical opposite of acids.
Answer:
The number of energy levels will increase.
Explanation:
As they are all Noble Gases, they are all in the same family. However, as you go further down the list of Noble Gases, the period number increases. The period number shows the number of energy levels. Hence, an increase in energy levels.