Question

1. consider the following elements - calcium, bromine, and rubidium - that were not tested in the lab.

what properties would you expect them to have? (hint: consider their location on the periodic table.) for each element, circle two properties that you predict they might have.
calcium (atomic #20)
shiny
conducts electricity
dull
silver/gray
brittle
malleable
reactivity with hcl?
bromine (atomic #35)
shiny
conducts electricity
dull
silver/gray
brittle
malleable
reactivity with hcl?
rubidium (atomic #37)
shiny
conducts electricity
dull
silver/gray
brittle
malleable
reactivity with hcl?

Explanation:

Step1: Analyze Calcium's properties

Calcium is a metal. Metals are generally shiny, malleable, and conduct electricity. Calcium is also reactive with HCl (as metals in groups 1 and 2 react with acids).

Step2: Analyze Bromine's properties

Bromine is a non - metal. Non - metals are usually dull (in solid state, bromine is a liquid at room temperature but in terms of typical non - metal properties), brittle (if solid), and do not conduct electricity well. Bromine is not reactive with HCl in the same way as metals (it has different chemical reactivity patterns).

Step3: Analyze Rubidium's properties

Rubidium is a metal (group 1 alkali metal). Metals are shiny, malleable, conduct electricity, and very reactive with HCl (group 1 metals are highly reactive with acids).

Answer:

Calcium: Shiny, Malleable, Conducts electricity, Reactive with HCl.
Bromine: Dull (if solid - like its solid form in some conditions, but as a liquid it has a different appearance, but non - metal properties imply dullness in solid state analogy), Brittle (if solid - non - metal solids are brittle), Does not conduct electricity well, Not reactive with HCl (in the metal - acid reaction sense).
Rubidium: Shiny, Malleable, Conducts electricity, Reactive with HCl.