Question

Определите массовую долю тетрагидроксоалюмината натрия в растворе, полученном при последовательном растворении в 220 мл воды 8,05г натрия и 8,1г алюминия.

Answer 1

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Answer 2

Calculation of the Mass Fraction of Sodium Tetrahydroxoaluminate in the Solution

To determine the mass fraction of sodium tetrahydroxoaluminate in the solution, we need to calculate the moles of sodium and aluminum in the solution first. Then, we can use the stoichiometry of the reaction between sodium and aluminum to find the moles of sodium tetrahydroxoaluminate formed. Finally, we can calculate the mass fraction by dividing the mass of sodium tetrahydroxoaluminate by the total mass of the solution.

Let's go step by step:

1. Calculate the moles of sodium (Na): - Given mass of sodium: 8.05 g - Molar mass of sodium (Na): 22.99 g/mol - Moles of sodium (Na) = mass of sodium (Na) / molar mass of sodium (Na)

2. Calculate the moles of aluminum (Al): - Given mass of aluminum: 8.1 g - Molar mass of aluminum (Al): 26.98 g/mol - Moles of aluminum (Al) = mass of aluminum (Al) / molar mass of aluminum (Al)

3. Determine the limiting reactant: - To find the limiting reactant, we compare the moles of sodium (Na) and aluminum (Al) and identify the reactant that is present in a lower amount. The reactant that is completely consumed in the reaction is the limiting reactant.

4. Calculate the moles of sodium tetrahydroxoaluminate (NaAl(OH)4): - The balanced chemical equation for the reaction between sodium and aluminum is: 8Na + 4Al + 18H2O -> 8NaAl(OH)4 + 3H2 - From the stoichiometry of the reaction, we can see that 8 moles of sodium react with 4 moles of aluminum to form 8 moles of sodium tetrahydroxoaluminate. - Since we have determined the limiting reactant in the previous step, we can use its moles to calculate the moles of sodium tetrahydroxoaluminate formed.

5. Calculate the mass of sodium tetrahydroxoaluminate (NaAl(OH)4): - Given volume of water: 220 mL - Density of water: 1 g/mL (approximately) - Mass of water: volume of water x density of water - Total mass of the solution = mass of sodium + mass of aluminum + mass of water - Mass fraction of sodium tetrahydroxoaluminate = mass of sodium tetrahydroxoaluminate / total mass of the solution

Let's perform the calculations:

1. Calculate the moles of sodium (Na): - Moles of sodium (Na) = 8.05 g / 22.99 g/mol

2. Calculate the moles of aluminum (Al): - Moles of aluminum (Al) = 8.1 g / 26.98 g/mol

3. Determine the limiting reactant: - Compare the moles of sodium (Na) and aluminum (Al) to identify the limiting reactant.

4. Calculate the moles of sodium tetrahydroxoaluminate (NaAl(OH)4): - Use the stoichiometry of the reaction to calculate the moles of sodium tetrahydroxoaluminate formed.

5. Calculate the mass of sodium tetrahydroxoaluminate (NaAl(OH)4): - Calculate the mass of water using the given volume and density. - Calculate the total mass of the solution. - Calculate the mass fraction of sodium tetrahydroxoaluminate.

Unfortunately, the search results provided do not contain the necessary information to determine the molar mass of sodium tetrahydroxoaluminate or the stoichiometry of the reaction. Without this information, it is not possible to accurately calculate the mass fraction of sodium tetrahydroxoaluminate in the solution.