Which of the following are molecules? Which of them are both molecules and compounds? oxygen (O2), carbon dioxide (CO2), sulfuric acid (H2SO4), ozone (O3), nitrogen (N2)
Hydrogen (H2), salt (NaCl), vinegar (C2H4O2), ammonia (NH3), baking soda (NaHCO3), methane (CH4)

11. phosphorus-32 is radioactive and has a half life of 14 days. how much of a 124 mg sample of phosphorus-32 is present after 56 days? a) 7.75 mg b) 15.5 mg c) 31.0 mg d) 62.0 mg

Joe shines white light into a bowl half full of water at an angle of incident of 27.5°. calculate the angle of refraction in the water given the indices of refraction for air and water are 1.00 and 1.36, respectively.

In what way do investigations build scientific knowledge? the results of investigations lead to questions that cannot be tested. they reflect the opinions and social values of scientists, ensuring valid information. the results of investigations lead to new questions, which lead to new investigations. they are not influenced by the research of earlier scientists, so they are able to address gaps in understanding.i