The answer to this question is: The pressure will be increased two times
The gas law includes an interaction of pressure(p), volume(V) and temperature(T). In this case, the gas has same amount and volume but then the temperature is doubled. The calculation would be:
p1 * V1 / T1= p2*V2 /T2
p1 * 1 / 1 = p2 * 1 / 2
p1 / (1/2)=p2
p2= 2* p1
It was due to the metal foil in which the alpha particles can't even pass through. This experiment conducted by Rutherford led to the discovery of protons.
To find the number of neutrons, you subtract the atomic number from the mass number of element X. So in this case, it'll be 151-44= the number of neutrons.