Question

1. choose the best answer. which of these produce the most vibrant colors when exposed to flame? alkaline earth transition alkali 16. choose the best answer. which of these element groups includes many metals like copper, silver, and gold? alkaline earth transition alkali

Explanation:

1. For question 15: Alkali metals are known for producing intense, vibrant flame test colors due to the easy excitation of their single valence electron. Alkaline earth metals produce less distinct colors, and transition metals do not typically produce vibrant flame test colors compared to alkali metals.
2. For question 16: Copper, silver, and gold are all well-known transition metals, which occupy the d-block of the periodic table. Alkaline earth and alkali metals are in the s-block and do not include these elements.

Answer:

1. alkali
2. transition