Answer:
128 g/mol
Explanation:
The molar mass is how much a mol of the substance weight.
In this question the weight is given (1.570 g).
To find the number of moles in the sample, we use the ideal gas law: PV=RnT
P= 1atm
V= 577mL= 0.577L
R (universal gas constant)= 0.08206(
)
n= number of moles
T= 300°C= 573.15K
Solving for n:
n= 
<em>k</em>
n=0.0123mol
Molar mass=
Molar mass=128
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 :
I believe B) in both chemical changes and physical changes since in chemical changes, nothing is created or destroyed. In physical changes same thing but with matter.
