Answer:
The presence of neutrons
Explanation:
Based on gold foil experiments, Rutherford proposed a atomic model known as Rutherford'd model or nuclear model or planetary model of the atom.
As per this model, most of the mass of the atom is concentrated in the center of the atom known as nucleus.
Electrons revolve around it same as planet revolve around sun.
Since, neutrons had not been discovered at the time of Rutherford'd model, therefore, as per the Rutherford'd model, nucleus is only made of protons.
Therefore, the correct option is option B
<span>It’s temp will remain at 0 degrees Celsius until all the ice Melts
</span>
Answer:
pure substance : lead ( Pb )
mixture substance : nitrogen ( N )
Answer:
Solution:-
The gas is in the standard temperature and pressure condition i.e. at S.T.P
Therefore,
V
i
=22.4dm
3
V
f
=?
As given that the expansion is isothermal and reversible
∴ΔU=0
Now from first law of thermodynamics,
ΔU=q+w
∵ΔU=0
∴q=–w
Given that the heat is absorbed.
∴q=1000cal
⇒w=−q=−1000cal
Now,
Work done in a reversible isothermal expansion is given by-
w=−nRTln(
V
i
V
f
)
Given:-
T=0℃=273K
n=1 mol
∴1000=−nRTln(
V
i
V
f
)
⇒1000=−1×2.303×2×273×log(
22.4
V
f
)
Explanation:
Answer:
0.453 moles
Explanation:
The balanced equation for the reaction is:
2Fe(s) + 3O2(g) ==> 2Fe2O3
From the equation, mass of O2 involved = 16 x 2 x 3 = 96g
mass of Fe2O3 involved = [(2x26) + 3 x 16] x 2
= 100g
Therefore 96g of O2 produced 100g of Fe2O3
32.2g of O2 Will produce 100x32.2/96
= 33.54g of Fe2O3
Converting it to mole using number of mole = mass/molar mass
but molar mass of Fe2O3 = 26 + (16 X 3)
= 74g/mole
Therefore number of mole of 33.54g of Fe2O3 = 33.54/74
= 0.453 moles
