Answer is (4) - Pb.
According to the reactivity series of elements
- the elements which are above the hydrogen are more reactive than hydrogen.
- the elements which are below the hydrogen are less reactive than hydrogen.
Among the given choices, only Pb is placed above the hydrogen in the reactivity series and rest are below the hydrogen.
Hence, Pb is more active than hydrogen.
Answer:
Chemical to electrical to mechanical
Explanation:
The energy conversion going on in a battery - powered toy car is from chemical to electrical and then to mechanical energy.
According to the law of conservation of energy, energy is neither created nor destroyed but transformed from one form to another.
- A battery is a cell that is capable of producing electrical energy from chemical actions.
- This electrical energy is used to power rotors in the toy car which cause the mechanical motion of the device.
Answer:Explanation:
The Roman numeral must have the same value as the charge of the ion. In our example, the transition metal ion Fe2+ would have the name iron(II). Add the name of the anion to the transition metal ion. In our example, FeCl2 would have the name iron(II) chloride since the anion is Cl-, which has the name chloride.
Because if you change the subscripts you can change the whole equestion and can get the wrong balance therefore instead of change subscripts you supports to change the coefficients and coefficients is an among of the rule in balance of chemical equestion.
Uranus's atmosphere is mostly composed of hydrogen and helium