Answer:
Iron -> Fe - Group 8
Silver -> Ag - Group 11
Mercury -> Hg - Group 12
Oxygen -> O - Group 16
Gold -> Au - Group 11
Potassium -> K - Group 1
Xenon -> Xe - Group 18
Magnesium -> Mg - Group 2
Hydrogen -> H - Group 1
Answer:
The platypus serves as a 'bridge' animal between nonmammals like birds and reptiles, which maintain their testicles in their body cavity, and placental and marsupial mammals, which hold their testes in an external scrotum."
Its when one species marries another species
The thermodynamic barrier that must be overcome before products are formed in spontaneous reaction is activation energy.
The activation energy is the maximum amount of extra energy that is required by a reacting molecules to get converted into product. It is the minimum energy that is required or needed to activate or energize molecules or atoms.
It is needed in the reaction so that reactants can move together and overcome forces of repulsion and start bond breaking.
Reactant is the substance that takes part in and that undergoes change during a reaction.
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