What are two things required for something to be matter?

The mass of a neutron is equal to the mass of a proton plus the mass of an electron. true or false false true

8.98 dm3 of hydrogen gas is collected at 38.8 °c. find the volume the gas will occupy at -39.9 °c if the pressure remains constant.

Predict the relative bond lengths of the three carbon-oxygen bonds in the carbonate ion (co2−3). what would you expect the charge to be on each oxygen? match the words in the left column to the appropriate blanks in the sentences on the right. make certain each sentence is complete before submitting your answer.