What part of dalton’s atomic theory is disproved by the existence of isotopes?

Based on the law of conservation of energy, which statement is false? answer- energy is lost when machines dont work right

There is a single path for electrons. the current decreases when additional resistors are added. the current will be the same in each resistor. these statements best describe a(n) circuit.

Air can be considered a mixture. which statement does not explain why?