Which notation is used to represent an alpha particle?

The notation that is used to represent an alpha particle is 4.2 H [THAT IS, AN HELIUM ATOM].

Alpha particle is formed when a radioactive element undergoes an alpha radioactive decay. An alpha radioactive decay is the type of decay in which an atomic nucleus gives off an helium nucleus and is thereby transformed into another element, which has a mass number that is less than the original element. An alpha particle is an helium nucleus, which contains two positively charged proton and two neutral neutron; it has an overall charge of +2 and a mass number of 4.

the population of unionid mussels in the hudson river decreased after zebra mussels were introduced. zebra mussels, a nonnative species, competed with the unionid mussels for food. the zebra mussels were able to outcompete the unionid mussels, allowing the zebra mussel population to increase dramatically over six years. the unionid mussel population decreased due to a lack of food.

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