Number of atoms : 1.26 x 10²³
<h3>Further explanation </h3>
The mole is the number of particles(molecules, atoms, ions) contained in a substance
1 mol = 6.02.10²³ particles
Can be formulated
N=n x No
N = number of particles
n = mol
No = Avogadro's = 6.02.10²³
0.21 moles of Al, so n = 0.21
Number of atoms :

Answer:
The concentration of HI present at equilibrium is 0.471 M.
Explanation:
Answer:
=> 1366.120 g/mL.
Explanation:
To determine the formula to use in solving such a problem, you have to consider what you have been given.
We have;
mass (m) = 25 Kg
Volume (v) = 18.3 mL.
From our question, we are to determine the density (rho) of the rock.
The formula:

First let's convert 25 Kg to g;
1 Kg = 1000 g
25 Kg = ?

= 25000 g
Substitute the values into the formula:

= 1366.120 g/mL.
Therefore, the density (rho) of the rock is 1366.120 g/mL.