One of mercurys spectral lines has a wavelength of 6.234x10-7 m. what is the lines frecuency?

Which statement justifies that phosphine (ph3) is a polar molecule?

18. use the activity series to predict whether the following synthesis reaction will occur. write the chemical equations for the reaction if it's predicted to occur. (s) + o2(g) -> *note: it is possible.*

The diagram below shows the different phase transitions that occur in matter. which arrow represents the transition in which dew is formed?