After James Chadwick discovered the neutron, atomic theory expanded to include isotopes. Isotopes have many practical uses. For example, scientists use the relative amount of carbon-12 to carbon-14 in ancient bones to determine how old they are.

James Chadwick, like Emest Rutherford, had to infer that neutrons were present in atoms. He made inferences based on observations of the
behavior of atoms during experimental tests. Using evidence from Rutherford's gold foil experiment, defend the following claim: Scientific
knowledge is based on observation and inference

Explanation:

For four years, James Chadwick was a prisoner of war in Germany. ... But they and other researchers were finding that the proton did not ... atom). For example, a helium atom has an atomic mass of 4, but an atomic number (or positive charge) of 2. Since electrons have almost no mass, it seemed that something besides the ...

Just gonna take the second slot..

Explanation:

in theory, limestone is composed principally of the compound calcium carbonate - caco3, but in reality this compound is deposited in conditions involving a number of other compounds as impurities so it ends up being a mixture of many compounds.

hope this : -)

tony (lordcaos066)