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, 
, 
, 
, 
, 
, 
)
and a cube of salt with an edge of length 
are both increased at the same rate until the atom reaches the size of a tennis ball. The radius of the ball is equal to 
. What is the length of an edge of the cube after the increase?
. The electron is located at an average distance of 
from the centre of the nucleus. Calculate the proportion of the volume of the atom occupied by the volume of the nucleus.
helium gas is kept in a cylindrical jar at a pressure of 
and temperature of 
. Calculate the number of each of protons, neutrons and electrons in the helium in the jar?
; 
)
and 
with corresponding proportions of 75.78 % and 24.22 %. Calculate the relative atomic mass of chlorine.
if we know that its mass is 7.016003 u. The mass of the proton is 1.007276 and the mass of the neutron is 1.008665 u.
.
decays with the beta (positron) decay. Determine the decay products of this reaction using the periodic table.
less than the mass of the reactants.
fuses together with a Hydrogen atom nucleus. An element is formed, and at the same time, some energy is radiated in the form of a gamma ray during the reaction. Determine which element is created.
decays into two major parts and three neutrons. One of the decay products is the Barium isotope 
. Determine which other element is created.
when it is bombarded with neutrons?
:
is 222.0176 u, and the mass of the Helium nucleus is 4.0026 u.
.
is 1.007825 u, the mass of the neutron 1.008665 u and the mass of the Helium 
is 4.002602 u. Calculate how much energy is released in this reaction.
into elementary particles? The mass of the Helium nucleus is 4.00153 u, the mass of the proton is 1.007276 u, the mass of the neutron is 1.008665 u.
decomposes with the following decompositions in order:
of radioactive Thorium atoms decaying with a half-life of 12.4 years. After how long do we have 
atoms of this element left in the sample?
nuclei. After three days, there are still 
. Calculate the half-life of this element.
. This radioactive isotope of carbon is naturally present in the atmosphere and decays with a half-life of 5700 years. When the bones are found, they had 3.3 decays per second. The bones of living animals, on the other hand, have 30.8 decays per second. Estimate the age of the excavated bone.
-particle or a 
-particle to become a nucleus of a different element. This nucleus is also unstable and emits an 
-decay to form nuclide X. This decay may be represented by the equation shown.
and 
, respectively. What is a difference between hydrogen and deuterium?
-particles. The energy released in the decay process is the same for each nucleus that decays, but the 
decay to form nuclide Y. The decay may be represented by the equation shown.
decays through a sequence of emissions of 
and 
particles to form the stable nuclide 
. How many 
undergoes 
decay?
-decay.
-particles emitted from a radioactive sample have a continuous range of kinetic energies.
-decay to form nucleus Q. Nucleus Q then undergoes 
decay to form nucleus R. Nucleus P is represented by point P on the graph. Which point on the graph represents nucleus R?
and charge 
. What are the mass and charge of an antiproton?
-particles and 4 
-particles to form nucleus X. How can nucleus X be represented?
of a particle is given by the equation shown.
-particle, a 
-particle and a proton 
. Which list shows the particles in order of increasing magnitude of 
-particle emission, the 
particle emission, the 
is fired at a 
nucleus. The neutron is absorbed by the nucleus which then splits to form nuclei of 
and 
. What is the number of free neutrons emitted when the 
decay is correct?
