Here, we use the mole as we would use any other collective number: a dozen eggs; a Bakers' dozen; a Botany Bay dozen.
Of course, the mole specifies a much larger quantity, and if I have a mole of stuff then I have
6.022
×
10
23
individual items of that stuff. We can also specify an equivalent mass, because we also know the mass of a mole of iron, and a mole of oxygen etc........The mole is thus the link between the macro world of grams and kilograms and litres, that which we can measure out in the lab, to the micro world of atoms, and molecules, that which we can perceive only indirectly.
Here we have the formula unit
F
e
2
(
S
O
4
)
3
. If there is a mole of formula units, there are necessarily 2 moles of iron atoms, 3 sulfate ions,.......etc.
Answer : The density of an object is, 
Solution : Given,
Mass of an object = 60 g
Volume of an object = 
Formula used :
Now put all the given values in this formula, we get the density of an object.
Therefore, the density of an object is,
Answer: There are four atoms
Explanation: mass of Cl atom is 35.45 amu
Amount of atoms n = m/M = 142 / 35.45 = 4
H2S donates a proton, therefore it is a Brønsted-Lowry base; CH3NH2 accepts a proton, so it’s a Brønsted-Lowry base.
Answer:
The principle of superposition states that the oldest rock units are at rock bottom , and therefore the youngest are at the highest . Based on this, layer C is oldest, followed by B and A. So the full sequence of events is as follows: Layer C formed.
Explanation:
