Question

2. Задача: Рассчитайте объём водорода (н.у.), который образуется при взаимодействии 12 г натрия, содержащего 3% примесей с водой. Определите количество вещества щёлочи, которое получится при этом.

Answer 1

2Na+2H2O=2NaOH+H2
m(Na)=12*(100-3)/100=11,64г
M(Na)=23г/моль
n(Na)=11,64/23=0,51моль
nNa:nNaOH:nH2=2:2:1
n(NaOH)=0,51мо
n(H2)=0,51/2=0,255мол
V(H2)=22,4*0,255=5,712л

Answer 2

Calculation of Hydrogen Gas Volume

To calculate the volume of hydrogen gas (at standard temperature and pressure) produced when 12 grams of sodium reacts with water containing 3% impurities, we need to consider the balanced chemical equation for the reaction.

The balanced chemical equation for the reaction between sodium and water is:

2Na + 2H2O -> 2NaOH + H2

From the equation, we can see that for every 2 moles of sodium (Na) reacting, 1 mole of hydrogen gas (H2) is produced.

To find the number of moles of sodium (Na) in 12 grams, we can use the molar mass of sodium, which is 22.99 g/mol.

Number of moles of sodium (Na) = Mass of sodium (g) / Molar mass of sodium (g/mol) Number of moles of sodium (Na) = 12 g / 22.99 g/mol

Now, we can calculate the number of moles of hydrogen gas (H2) produced using the mole ratio from the balanced equation.

Number of moles of hydrogen gas (H2) = Number of moles of sodium (Na) / 2

To find the volume of hydrogen gas (H2) at standard temperature and pressure (STP), we can use the ideal gas law, which states that:

PV = nRT

Where: P = Pressure (in atm) V = Volume (in liters) n = Number of moles R = Ideal gas constant (0.0821 L·atm/(mol·K)) T = Temperature (in Kelvin)

At STP, the pressure is 1 atm and the temperature is 273.15 K.

Now, we can calculate the volume of hydrogen gas (H2) using the ideal gas law:

Volume of hydrogen gas (H2) = (Number of moles of hydrogen gas (H2) * R * T) / P

Substituting the values into the equation, we can calculate the volume of hydrogen gas (H2) produced.

Please note that the calculation assumes ideal conditions and does not take into account any other factors that may affect the reaction.

Let's perform the calculations now.