Question

ПОМОГИТЕ ПОЖАААЛУЙСТА! Кальций массой 8 грамм.Полностью прореагировал с водой.Полученный гидроксид нейтрализовали азотной кислотой.Рассчитайте количество вещества и массу образовавшейся соли.

Answer 1

Ca   +       2H2O   =    Са(ОН)2     +     Н2

ню=1моль                   ню=1моль

M=40г/моль                М=74г/моль

m=40г                         m=74г

Mr(Са(ОН)2)=40+32+2=74

8г------хг

40г-----74г

х=74*8/40=14,8г

Ca(OH)2     +    2HNO3  = Ca(NO3)2   +    2H2O

ню=1моль                         ню=1моль

М=74г/моль                      М=164г/моль

m=74г                               m=164г

Mr(Ca(NO3)2)=40+28+96=164

14,8г----------хг

74г-------------164г

х=164*14,8/74=32,8

ответ:32,8г

Answer 2

Calculation of the Amount of Substance and Mass of the Formed Salt

To calculate the amount of substance and mass of the formed salt, we need to follow the given steps:

1. Determine the balanced chemical equation for the reaction between calcium and water. The balanced equation is as follows:

Ca + 2H2O → Ca(OH)2 + H2

2. Calculate the amount of substance of calcium (Ca) using its molar mass. The molar mass of calcium is 40.08 g/mol.

Given mass of calcium = 8 g Amount of substance of calcium = (given mass of calcium) / (molar mass of calcium)

Amount of substance of calcium = 8 g / 40.08 g/mol

3. From the balanced equation, we can see that 1 mole of calcium reacts with 2 moles of water to form 1 mole of calcium hydroxide (Ca(OH)2).

Therefore, the amount of substance of calcium hydroxide formed is equal to the amount of substance of calcium.

4. Calculate the molar mass of calcium hydroxide (Ca(OH)2). The molar mass of calcium is 40.08 g/mol, oxygen is 16.00 g/mol, and hydrogen is 1.01 g/mol.

Molar mass of calcium hydroxide = (molar mass of calcium) + 2 * (molar mass of oxygen) + 2 * (molar mass of hydrogen)

5. Calculate the mass of calcium hydroxide formed using the amount of substance of calcium hydroxide and its molar mass.

Mass of calcium hydroxide = (amount of substance of calcium hydroxide) * (molar mass of calcium hydroxide)

6. The formed calcium hydroxide is then neutralized with nitric acid (HNO3). The balanced equation for the neutralization reaction is:

Ca(OH)2 + 2HNO3 → Ca(NO3)2 + 2H2O

7. From the balanced equation, we can see that 1 mole of calcium hydroxide reacts with 2 moles of nitric acid to form 1 mole of calcium nitrate (Ca(NO3)2).

Therefore, the amount of substance of calcium nitrate formed is equal to the amount of substance of calcium hydroxide.

8. Calculate the molar mass of calcium nitrate (Ca(NO3)2). The molar mass of calcium is 40.08 g/mol, nitrogen is 14.01 g/mol, and oxygen is 16.00 g/mol.

Molar mass of calcium nitrate = (molar mass of calcium) + 2 * (molar mass of nitrogen) + 6 * (molar mass of oxygen)

9. Calculate the mass of calcium nitrate formed using the amount of substance of calcium nitrate and its molar mass.

Mass of calcium nitrate = (amount of substance of calcium nitrate) * (molar mass of calcium nitrate)

Please note that without the specific molar mass of the formed salt, it is not possible to provide an exact numerical answer. However, you can use the above steps to calculate the amount of substance and mass of the formed salt once you have the molar mass of the salt.

Let me know if there is anything else I can help you with!