One mole is always the same number: 6.02 * 10^ 23.
So, one mole of cars = 6.02 * 10 ^23 cars; one mole of pencils = 6.02 * 10^23 pencils; one mole of atoms = 6.02 * 10^23 atoms; one mole of molecules = 6.02 * 10^23 molecules.
So, all the options are correct: one mole of calcium ions has 6.02 * 10^23 representative particles, such as one mole of calcium nuclei and one of calcium atoms.
Answer: You're converting electrical energy from the wall outlet into chemical energy inside the battery, plus a bit of wasted heat energy, since battery charging is less than 100% efficient.
I’m assuming the top ruler has more measurement points, like more specific numbers. This would mean the top ruler is more reliable because you can be more specific with your measurements
Fractional distillation is the process by which oil refineries separate crude oil into different, more useful hydrocarbon products based on their relative molecular weights in a distillation tower.