Answer true or false.
(a) The majority (greater than $50 \%$ ) of the more than 300 naturally occurring isotopes are stable.
(b) More artificial isotopes have been created in the laboratory than there are naturally occurring stable isotopes.
(c) All artificial isotopes created in the laboratory are radioactive.
(d) The terms "beta particle," "beta emission," and "beta ray" all refer to the same type of radiation.
(e) When balancing a nuclear equation, the sum of the mass numbers and the sum of the atomic numbers on each side of the equation must be the same.
(f) The symbol of a beta particle is $_{-1}^{0} \beta$
(g) When a nucleus emits a beta particle, the new nucleus has the same mass number but an atomic number one unit higher.
(h) When iron-59 $\left(\frac{59}{26} \mathrm{Fe}\right)$ emits a beta particle, it is converted to cobalt- $59\left(\frac{59}{27} \mathrm{Co}\right)$
(i) When a nucleus emits a beta particle, it first captures an electron from outside the nucleus and then emits it.
(j) For the purposes of determining atomic numbers in a nuclear equation, an electron is assumed to have a mass number of zero and an atomic number of -1
(k) The symbol for an alpha particle is $_{2}^{4} \mathrm{He}$
(1) When a nucleus emits an alpha particle, the new nucleus has an atomic number two units higher and a mass number four units higher.
(m) When uranium- $238\left(^{238} \mathrm{U}\right)$ undergoes alpha emission, the new nucleus is thorium- $234\left(\frac{234}{90} \mathrm{Th}\right)$
(n) The symbol of a positron is $+1 \beta$
(o) A positron is sometimes referred to as a positive electron.
(p) When a nucleus emits a positron, the new nucleus has the same mass number but an atomic number one unit lower.
(q) When carbon-11 $\left(\frac{11}{6} \mathrm{C}\right)$ emits a positron, the new nucleus formed is boron-11 $\left(_{5}^{11} \mathrm{B}\right)$
(r) Alpha emission and positron emission both result in the formation of a new nucleus with a lower atomic number.
(s) The symbol for gamma radiation is $\gamma$
(t) When a nucleus emits gamma radiation, the new nucleus formed has the same mass number and the same atomic number.
(u) When a nucleus captures an extranuclear electron, the new nucleus formed has the same atomic number but a mass number one unit lower.
(v) When gallium-67 $\left(\begin{array}{l}67 \\ 31\end{array}\right)$ undergoes electron capture, the new nucleus formed is germanium-67 $\left(_{32}^{67} \mathrm{Ge}\right)$