Answer:
~69.744 moles of Ca
Explanation:
Using Avogadro's constant , we know that:
1 mole = 6.022 x 10^23 atoms
S0, the number of moles in 4.20 x 10^25 atoms of Ca:
=(4.20 x 10^25 x 1 )/(6.022 x 10^23)
~69.744 moles of Ca
Q2:How many atoms are in 0.35 moles of oxygen?
1 mole = 6.022 x 10^23 atoms
S0, the number of atoms in 0.35 moles of oxygen:
=[0.35 x (6.022 x 10^23)]
=2.1077 x 10^23 atoms of Oxygen
Hope it helps:)
C) Nucleus...... Hope it helps, Have a nice day :)
The volume of nitrogen monoxide that occupy at STP is= 277 Ml
calculation
The volume is obtained using the combined gas law that is P1V1/T1= P2V2?
Where P1 = 720 MmHg
V1 = 400ml
T1= 100 +273= 373 K
At STP temperature = 273 K and pressure= 760 mm hg
therefore T2= 273 k
p2 = 760 mmhg
V2=?
make V2 the subject of the formula
V2= (T2 ×P1 ×V1)/(P2×T1)
V2 is therefore = (273k x720 mmhg x 400 ml)/(760 mmhg x373K) = 277 Ml
Mass of iron chloride (FeCl₂) : 22.68 g
<h3>Further explanation</h3>
Proust stated the Comparative Law that compounds are formed from elements with the same Mass Comparison so that the compound has a fixed composition of elements
In the same compound, although from different sources and formed by different processes, it will still have the same composition/comparison
With this law, we can calculate how many grams an element is needed to make a compound with a certain mass, as desired
<h3 />

The iron ions in 50 g mixture :

