The mass of dinitrogen in grams produced by the thermal decomposition of 2 moles of ammonium dichromate.

Explanation

To find the mass of dinitrogen (N₂) produced by the thermal decomposition of 2 moles of ammonium dichromate (NH₄)₂Cr₂O₇, we can follow these steps:

### Step 1: Write the balanced chemical equation for the thermal decomposition of ammonium dichromate.

The balanced equation for the thermal decomposition of ammonium dichromate is:
\[ 2 \, (NH_4)_2Cr_2O_7 \, \text{(s)} \rightarrow 2 \, N_2 \, \text{(g)} + 4 \, H_2O \, \text{(g)} + Cr_2O_3 \, \text{(s)} \]

### Step 2: Determine the amount of dinitrogen produced from 2 moles of ammonium dichromate.

From the balanced equation, we can see that 2 moles of ammonium dichromate produce 2 moles of dinitrogen. Therefore, if we start with 2 moles of ammonium dichromate, we will produce:
\[ 2 \, \text{moles of } N_2 \]

### Step 3: Calculate the mass of dinitrogen produced.

To find the mass of dinitrogen produced, we need to use the molar mass of dinitrogen (N₂). The molar mass of nitrogen (N) is approximately 14 g/mol, so the molar mass of dinitrogen (N₂) is:
\[ M(N_2) = 2 \times 14 \, \text{g/mol} = 28 \, \text{g/mol} \]

Now, we can calculate the mass of 2 moles of dinitrogen:
\[ \text{Mass of } N_2 = \text{Number of moles} \times \text{Molar mass} \]
\[ \text{Mass of } N_2 = 2 \, \text{moles} \times 28 \, \text{g/mol} = 56 \, \text{g} \]

### Final Answer:
The mass of dinitrogen produced by the thermal decomposition of 2 moles of ammonium dichromate is **56 grams**.

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