Question

Закончите уравнения реакций и расставьте коэффициенты методом электронного баланса: а) Pb + HNO3(разб.) → б) Pb + HNO3(конц.) → в) Рb + Н2O + КОН→

Answer 1

1) 3 Pb + 8 HNO3 = 3 Pb(NO3)2 + 2 NO + 4 H2O
2) Pb + 4HNO3(к) => Pb(NO3)2 + 2NO2 + 2H2O
3) не знаю

Answer 2

а) Pb + HNO3(разб.) →

To balance the equation, we need to ensure that the number of atoms of each element is the same on both sides of the equation. Let's balance the equation step by step:

1. Start by balancing the atoms that appear in the fewest compounds. In this case, we have one lead (Pb) atom on the left side and one on the right side, so we don't need to balance it further.

2. Next, let's balance the nitrogen (N) atoms. We have one nitrogen atom in the nitric acid (HNO3) on the left side. To balance it, we need to put a coefficient of 2 in front of the nitric acid on the left side:

Pb + 2HNO3(разб.) →

3. Now, let's balance the oxygen (O) atoms. We have 3 oxygen atoms in the nitric acid (HNO3) on the left side. To balance it, we need to put a coefficient of 3 in front of the water (H2O) on the right side:

Pb + 2HNO3(разб.) → Pb(NO3)2 + 3H2O

The balanced equation is: Pb + 2HNO3(разб.) → Pb(NO3)2 + 3H2O.

б) Pb + HNO3(конц.) →

To balance this equation, we follow the same steps as before:

1. Start by balancing the atoms that appear in the fewest compounds. In this case, we have one lead (Pb) atom on the left side and one on the right side, so we don't need to balance it further.

2. Next, let's balance the nitrogen (N) atoms. We have one nitrogen atom in the nitric acid (HNO3) on the left side. To balance it, we need to put a coefficient of 2 in front of the nitric acid on the left side:

Pb + 2HNO3(конц.) →

3. Now, let's balance the oxygen (O) atoms. We have 3 oxygen atoms in the nitric acid (HNO3) on the left side. To balance it, we need to put a coefficient of 3 in front of the water (H2O) on the right side:

Pb + 2HNO3(конц.) → Pb(NO3)2 + 3H2O

The balanced equation is: Pb + 2HNO3(конц.) → Pb(NO3)2 + 3H2O.

в) Рb + Н2O + КОН →

To balance this equation, we follow the same steps as before:

1. Start by balancing the atoms that appear in the fewest compounds. In this case, we have one lead (Pb) atom on the left side and one on the right side, so we don't need to balance it further.

2. Next, let's balance the hydrogen (H) atoms. We have 2 hydrogen atoms in water (H2O) on the left side. To balance it, we need to put a coefficient of 2 in front of the potassium hydroxide (KOH) on the right side:

Pb + H2O + 2KOH →

3. Now, let's balance the oxygen (O) atoms. We have 1 oxygen atom in water (H2O) on the left side and 2 oxygen atoms in potassium hydroxide (KOH) on the right side. To balance it, we need to put a coefficient of 2 in front of water (H2O) on the left side:

Pb + 2H2O + 2KOH →

The balanced equation is: Pb + 2H2O + 2KOH →.