Question

Помогите. Дам 50 баллов. Объясните как составить уравнение реакции и найти пропущенные вещества с помощью метода электронного баланса NaCrO2+...+ NaOH=...+ NaBr + H2O

Answer 1

Cr(+3) в щелочной среде окисляется до Cr(+6)
Cr-восстановитель
Br-окислитель
Составим уравнение
NaCrO2 + Br2 + NaOH ---> CrO3 + NaBr + H2O

Cr(+3) -3e -->Cr(+6) |2|
Br2(0) +2e --> 2Br |3|
 Расставим коэффициенты:
2NaCrO2 + 3Br2 + 4NaOH = 2CrO3 + 6NaBr + 2H2O
(т.к. в правой части уравнения 6 атомов Na,то уравниваем поставив 4 к щелочи(NaOH),затем уравняем водород поставив 2 к воде.Проверим кол-во кислорода: 4O+4O = 6O + 2O  8О=8О Кислород уравнен)

Answer 2

Understanding the Reaction Equation and Balancing Chemical Equations

To understand how to balance a chemical equation and find the missing substances using the method of electronic balancing, let's break down the given reaction equation:

NaCrO2 + NaOH = NaBr + H2O

In this equation, we have two reactants on the left side (NaCrO2 and NaOH) and two products on the right side (NaBr and H2O). The goal is to balance the equation by ensuring that the number of atoms of each element is the same on both sides of the equation.

Balancing the Equation

To balance the equation, we need to follow these steps:

1. Start by counting the number of atoms of each element on both sides of the equation. - On the left side: - Sodium (Na): 1 - Chromium (Cr): 1 - Oxygen (O): 2 - Hydrogen (H): 1 - On the right side: - Sodium (Na): 1 - Bromine (Br): 1 - Oxygen (O): 1 - Hydrogen (H): 2

2. Identify the elements that are not balanced. In this case, we can see that the number of oxygen atoms is not balanced.

3. To balance the oxygen atoms, we can add a coefficient in front of the water (H2O) on the right side. Let's add a coefficient of 2 to balance the oxygen atoms.

NaCrO2 + NaOH = NaBr + 2H2O

4. Now, let's recheck the number of atoms of each element: - On the left side: - Sodium (Na): 2 - Chromium (Cr): 1 - Oxygen (O): 2 - Hydrogen (H): 1 - On the right side: - Sodium (Na): 1 - Bromine (Br): 1 - Oxygen (O): 4 - Hydrogen (H): 4

5. The number of sodium and hydrogen atoms is not balanced. To balance them, we can add a coefficient of 2 in front of NaOH on the left side.

2NaCrO2 + 2NaOH = NaBr + 2H2O

6. Now, let's recheck the number of atoms of each element: - On the left side: - Sodium (Na): 4 - Chromium (Cr): 2 - Oxygen (O): 6 - Hydrogen (H): 4 - On the right side: - Sodium (Na): 1 - Bromine (Br): 1 - Oxygen (O): 4 - Hydrogen (H): 4

7. The number of sodium and chromium atoms is not balanced. To balance them, we can add a coefficient of 4 in front of NaBr on the right side and a coefficient of 2 in front of NaCrO2 on the left side.

2NaCrO2 + 2NaOH = 4NaBr + 2H2O

8. Finally, let's recheck the number of atoms of each element: - On the left side: - Sodium (Na): 8 - Chromium (Cr): 2 - Oxygen (O): 6 - Hydrogen (H): 4 - On the right side: - Sodium (Na): 4 - Bromine (Br): 4 - Oxygen (O): 6 - Hydrogen (H): 4

Now, the equation is balanced, and the