Explanation:
magnesium and sodium because they are minerals and part of iron
Answer:
the number of protons and neutrons at both terminals are equal
Explanation:
When the number of positive charge and negative charge are both equally the terminal, it becomes neutral and out of charge, because first it undergo enough chemical reaction and there is no remaining tendency for positive and negative charges to get separated. When this tendency dies, the battery also will run out of charge.
Answer:
the wavelength of radiation emitted is 
Explanation:
The energy of the Bohr's hydrogen atom can be expressed with the formula:

For n = 7:


For n = 4


The electron goes from the n = 7 to the n = 4, then :


Wavelength of the radiation emitted:

where;
hc = 1242 eV.nm


Water on earth can exist in all 3 states: solid, liquid, and gas.
Earth is just the right distance from the sun so that temperatures are ideal for living organisms.
Earth has a protective atmosphere shielding the planet from harmful UV and X rays.
Answer: the protons n neutrons
Explanation: