State two properties of group I elements.

Explanation

**Step-by-Step Text Solution:**

1. **Identify the Group**: Group I elements are also known as alkali metals. This group includes elements such as lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), and francium (Fr).

2. **Property 1 - Valence Electrons**: All Group I elements have one valence electron. This means that they have a single electron in their outermost shell. For example, sodium (Na) has the electronic configuration of 2, 8, 1, indicating that it has one valence electron.

3. **Property 2 - Softness**: Group I elements are characterized as soft metals. They can be easily cut with a knife and have relatively low melting points compared to other metals.

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