Respuesta :
To go to mass to number of particles, these are the steps:
Mass divided by molar mass gives moles
moles x avogadros number [will be using 6.02x10^23] gives number of particles.
So:
1.72/128.17 = 0.0134 moles.
0.0134 x 6.02x10^23= 8.07xx10^21 molecules of naphthalene. [rounded to 3 significant figures]
Mass divided by molar mass gives moles
moles x avogadros number [will be using 6.02x10^23] gives number of particles.
So:
1.72/128.17 = 0.0134 moles.
0.0134 x 6.02x10^23= 8.07xx10^21 molecules of naphthalene. [rounded to 3 significant figures]
Answer: [tex]0.0809\times 10^{23}[/tex]
Explanation:
According to avogadro's law, 1 mole of every substance weighs equal to the molecular mass and contains avogadro's number [tex]6.023\times 10^{23}[/tex] of particles.
To calculate the number of moles, we use the equation:
[tex]{\text{Number of moles}}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex]
[tex]{\text{Number moles}}=\frac{1.72g}{128g/mol}=0.0134moles[/tex]
1 mole of napthalene [tex]C_{10}H_8[/tex] contains =[tex]6.022\times 10^{23}[/tex] molecules
Thus 0.0134 moles of napthalene [tex]C_{10}H_8[/tex] contain=[tex]\frac{6.022\times 10^{23}}{1}\times 0.0134=0.0809\times 10^{23}[/tex] molecules
Thus there are [tex]0.0809\times 10^{23}[/tex] napthalene molecules.
