Which of these statements is incorrect regarding an atom of the element scandium?
a. it has 21 negatively charged electrons
b. it has 21 positively charged protons in its nuclear
c. it has 21 neutrons in its nucleus
d. its chemical symbol is sc

Here’s one way to follow the scientific method. place the missing steps in the correct position in the process

If you chip a tooth, most likely you will go to the dentist to have the missing material filled in. currently the material used to fill in teeth is a polymer that is flexible when put in, yet is hardened to the strength of a tooth after irradiation with blue light at a wavelength of 461 nm. what is the energy in joules for a photon of light at this wavelength?

What is the percentage of hydrogen in nitrogen trihydride