What are the geometrices of:
i. Prop-1-yne
ii. But-2-yne
iii. Hept-2-en-5-yne

Explanation

To determine the geometries of the given compounds, we will analyze each compound step by step.

### Step 1: Prop-1-yne
1. **Identify the structure**: Prop-1-yne has three carbon atoms (C) and a triple bond between the first and second carbon atoms. The structure can be represented as:
\[ \text{C} \equiv \text{C} - \text{C} \]
2. **Determine the geometry**: The carbon atoms involved in the triple bond (C≡C) are linear due to the triple bond, which means the angle between the bonds is 180 degrees. The terminal carbon (the third carbon) is sp-hybridized, leading to a linear geometry around the triple bond.
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