Answer
a) $^{231}_{91}Pa$ -> $^{277}_{89}Ac + ^{4}_{2}He$
b) $^{241}_{95}Pa$ -> $^{237}_{93}Ac + ^{4}_{2}He$
c) $^{226}_{88}Ra$ -> $^{222}_{86}Rn + ^{4}_{2}He$
d) $^{252}_{99}Es$ -> $^{248}_{97}Bk + ^{4}_{2}He$
Work Step by Step
a) $^{231}_{91}Pa$ -> $^{277}_{89}Ac + ^{4}_{2}He$
b) $^{241}_{95}Pa$ -> $^{237}_{93}Ac + ^{4}_{2}He$
c) $^{226}_{88}Ra$ -> $^{222}_{86}Rn + ^{4}_{2}He$
d) $^{252}_{99}Es$ -> $^{248}_{97}Bk + ^{4}_{2}He$
