Which instrument, along with a telescope, allows study of the wavelengths of visible light coming from a star? a. a shortwave radio set b. a nuclear reactor c. a solar flare d. a spectrograph

Ahydrogen atom has 1 electron. how many bonds can hydrogen form? a) 1 b) 2 c) 3 d) 4 e) 5

In a laboratory, 1.55mg of an organic compound containing carbon, hydrogen, and oxygen is burned for analysis. this combustion resulted in the formation of 1.45mg of carbon dioxide and .89 mg of water. what is the empirical formula for this compound?

The chemical formula for emerald is be3al2(sio3)6.an emerald can be decided as