E=hc/l
E=
<span><span>E=<span>(6.626 x 10-34 J s)(3.0 x 108m/s )</span><span>=2.88 x 10-19J</span></span><span>6.90 x 10-7m</span></span>
Answer:
Kr is a Noble Gas. Na is an alkali metal. F is halogen.
Group 17 is halogens. Inert is Noble Gases. Odourless and colourless is Noble Gases. Alkali metals do not occur freely in nature. Alkali metals are malleable
Explanation:
Answer : The equilibrium constant for this reaction is, 
Explanation :
The given main chemical reaction is:
; 
The intermediate reactions are:
(1)
; 
(2)
; 
We are reversing reaction 1 and multiplying reaction 2 by 2 and then adding both reaction, we get:
(1)
; 
(2)
; 
Thus, the equilibrium constant for this reaction will be:


Thus, the equilibrium constant for this reaction is, 
Answer:
2 HCl + CaCO3 = CaCl2 + H2O + CO2
Explanation:
On the right side we have 2xCl, to get the same amount we will multiply HCl on the left side by 2.
This will give us 2xH on the left side; we also have 2xH on the right side ( in H2O).
On both sides we have 1x Ca; 1x C.
On the left side we have 3XO (in CaCO3), on the right side we have 1O in H20 and 2xO in CO2, so 3x O on the right side as well.
The reaction is balanced.
Answer: Option (D) is the correct answer.
Explanation:
Atomic number of chlorine is 17 and its electronic distribution is 2, 8, 7.
So, in order to attain stability it tends to gain one electron from a donor atom. Therefore, a chlorine ion is formed as
.
As it gains only one electron that is why, -1 charge occurs.
Whereas Ar is a noble gas with atomic number 18. As it has completely filled octet so it will be unreactive in nature as it is already stable.
Similarly, He is also a noble gas so it is unreactive in nature.
Atomic number of boron (B) is 5 with electronic distribution 2, 3. So, in order to attain stability it needs to lose 3 electrons.
Thus, we can conclude that Cl is the atom which tends to gain 1 valence electron from another atom in order to become stable.