By 'waves' do you mean sound waves? If so sound waves need to travel through things like solids, liquids and yup <u>gases. </u>When the waves travel they are vibrating the molecules in the matter. By doing this he molecules in solids are packed very tightly.
Answer:
A. we can use sulfuric acid to prepare PbSO4
Answer:
<em>The electrons in an atom can only occupy certain allowed energy levels to a lower one</em>, the excess energy is emitted as a photon of light, with its wavelength dependent on the change in electron energy. This is why an atom can only emit specific wavelengths of light and not every possible wavelength.
Convert the mass to moles .
85.1 g ÷ 20.18 g/mol = 4.21704658
convert the moles to molecules
4.2170 mol × 6.022^23 molecules/mol = 2.539^24
I’m pretty sure it’s A or C