The bonds formed by transition metals in lower oxidation states are .......... while those formed in higher oxidation states are ............

Explanation

To answer the question, we need to fill in the blanks regarding the types of bonds formed by transition metals in different oxidation states.

1. **Understanding the Oxidation States**: Transition metals can exhibit multiple oxidation states. Lower oxidation states typically involve a loss of fewer electrons, while higher oxidation states involve the loss of more electrons.

2. **Bonds in Lower Oxidation States**: In lower oxidation states, transition metals tend to form **ionic bonds**. This is because the lower oxidation state generally corresponds to a lower electronegativity, leading to a tendency to lose electrons and form cations that attract anions.

3. **Bonds in Higher Oxidation States**: In higher oxidation states, transition metals tend to form **covalent bonds**. This is due to the increased electronegativity associated with higher oxidation states, which allows these metals to attract electrons more strongly and share them with other atoms.

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