Which option describes a similarity and a difference between isotopes of an element?
a) same atomic number; different number of protons
b) same number of protons; different atomic number
c) same atomic number; different mass number
d) same mass number; different atomic number
e) same number of neutrons; same number of protons

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.

answer: they produce more slow than unicellular organisms.