The table below shows a list of radioisotopes and their half-lives.

A 2-columns table with 10 rows. Column 1 is labeled radioisotope. Column 2 is labeled half-life. Lithium-5, 3 times 10 to the negative 22 seconds; polonium-211, 0.516 seconds; Barium-139, 82.7 minutes; uranium-240, 14.1 hours; Bismuth-210, 5.012 days; uranium 232, 68.9 years; carbon-14, 5730 years; plutonium-239, 24,065 years; beryllium-10, 1.6 times 10 to the 5 years; uranium-238, 4.5 times 10 to the 9 years.

The radioisotope that has the longest half-life is the best to use in powering planet and space exploration vehicles because they can travel farther. Which radioisotope is the best to use?
lithium-5
uranium-240
carbon-14
plutonium-239

b..

is the correct one

explanation:

covalent bonds form as valence electrons are shared between two atoms. lewis structures and structural formulas are common ways of showing the covalent bonding in organic molecules. formal charge describes the changes in the number of valence electrons as an atom becomes bonded into a molecule.

b i think it’s a water wheel turning in a stream

the enthalpy of formation of water is given as -285.8kj/mol, which states that the enthalpy of formation is negative.

negative enthalpy of formation indicates that the heat is released during the reaction process. the heat is released from reaction to the surroundings the enthalpy is expressed with a negative sign with the energy given out in the reaction process.

the formation of water takes place by giving out heat which is -285.8 kj/mol.