You are given a pure substance that is shiny, hard and has a relatively high density, this substance is likely a ?
a- metalloid
b- nonmetal
c- metal
d- lanthanide

metal

Metalloids have properties intermediate between the metals and nonmetals.

They have low density and will melt at low temperatures. They can be shiny or dull.

Non-metals are very brittle and dull. They have low density (they   feel light for their size) and of weak strength

metals are silvery looking, high density and hard in its physical appearance.

The lanthanides have a bright silvery appearance. They are soft, they can be cut with a knife.

c)as speed changes, wavelength and frequency change.

everything changes!

what experimental evidence led scientists to change from the previous model to this one?

a few of the positive particles aimed at a gold foil seemed to bounce back.

the colors of light emitted from heated atoms had very specific energies.

experiments with water vapor showed that elements combine in specific proportions.

cathode rays were bent in the same way whenever a magnet was brought near them.