In the estimation of nitrogen by Kjeldahl's method, the compound is heated with ............ in presence of .............

Explanation

To answer the question regarding the estimation of nitrogen by Kjeldahl's method, we can break it down into the following steps:

### Step-by-Step Solution:

1. **Identify the Method**: The question refers to the Kjeldahl's method, which is a well-known technique for estimating nitrogen content in organic compounds.

2. **Heating the Compound**: In the Kjeldahl's method, the organic compound is heated with concentrated sulfuric acid (H₂SO₄). This strong acid is necessary to break down the organic material and convert nitrogen into a measurable form.

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