If 40g of Sodium (Na) completely reacts with 60g of Chlorine (Cl2), what is the mass of the products? O a О b • с O d 40 g 60 g 100 g 160 g

1 answer

To determine the mass of the products formed from the reaction between sodium (Na) and chlorine (Cl\(_2\)), we first need to recognize the reaction that occurs:

\[ 2 , \text{Na} + \text{Cl}_2 \rightarrow 2 , \text{NaCl} \]

In this reaction, 2 moles of sodium react with 1 mole of chlorine gas to produce 2 moles of sodium chloride (NaCl).

  1. Calculate moles of sodium and chlorine:

    • Molar mass of sodium (Na) is approximately 23 g/mol.
    • Molar mass of chlorine (Cl\(_2\)) is approximately 70.9 g/mol (2 x 35.45 g/mol).

    Moles of sodium: \[ \text{Moles of Na} = \frac{40 , \text{g}}{23 , \text{g/mol}} \approx 1.74 , \text{mol} \]

    Moles of chlorine: \[ \text{Moles of Cl}_2 = \frac{60 , \text{g}}{70.9 , \text{g/mol}} \approx 0.85 , \text{mol} \]

  2. Determine the limiting reactant: According to the balanced equation, 2 moles of Na reacts with 1 mole of Cl\(_2\). So, we need to consider the ratio:

    • From the available moles of Na: \( 1.74 , \text{mol Na} \) would require \( \frac{1.74}{2} = 0.87 , \text{mol Cl}_2 \).
    • We only have 0.85 mol Cl\(_2\), which means Cl\(_2\) is the limiting reactant.
  3. Calculate the mass of the products:

    • Since Cl\(_2\) is the limiting reactant, we will use it to find the amount of NaCl produced. For every 1 mole of Cl\(_2\), 2 moles of NaCl are produced.

    Moles of NaCl produced: \[ \text{Moles of NaCl} = 2 \times 0.85 , \text{mol Cl}_2 = 1.7 , \text{mol NaCl} \]

    Calculating the mass of NaCl produced:

    • Molar mass of NaCl is approximately 58.5 g/mol.

    Mass of NaCl: \[ \text{Mass of NaCl} = 1.7 , \text{mol} \times 58.5 , \text{g/mol} \approx 99.45 , \text{g} \]

  4. Total mass of reactants: \[ \text{Total mass of reactants} = 40 , \text{g (Na)} + 60 , \text{g (Cl}_2) = 100 , \text{g} \]

According to the law of conservation of mass, the mass of the products will equal the mass of the reactants. Thus, the mass of the products is:

100 g.

The correct answer is 100 g (option c).