Question

calculate the number of atoms in a 1.94 x 10^3 g sample of calcium

Answer 1

$n = \frac{m}{M}$

$n = \frac{1.94*10^3}{40.08}$

$n = 48.40 mol$

Then,

$N = n*Na$
$N = 48.40*6.02*10^{23}$
$N= 2.94*10^{25}$ atoms

Hope this helps !

Photon

Answer 2

Answer:

1.94 *10^3 grams calcium contains 2.9*10^25 calcium atoms

Explanation:

Step 1: Data given

Mass of Calcium = 1.94 *10³ grams = 1940 grams

Molar mass of Calcium = 40.08 g/mol

Number of Avogadro = 6.022 * 10^23 / mol

Step 2: Calculate moles of Calcium

Moles Calcium = mass calcium / molar mass Calcium

Moles Calcium = 1940 grams / 40.08 g/mol

Moles Calcium = 48.40 moles

Step 3: Calculate number of atoms

Number of Calcium atoms = moles calcium * Number of Avogadro

Number of Calcium atoms = 48.40 moles * 6.022 *10^23 / mol

Number of Calcium atoms = 2.9 *10^25 atoms

1.94 *10^3 grams calcium contains 2.9*10^25 calcium atoms