I think its A because some scientist from the Department of Physics of Northeastern University found out that is not a part of Dalton's atomic theory.
Answer:
38.9 grams of 
Explanation:
0.187 mol BaCl2 x 
0.187 m x 208 g/m
0.187 x 208 g
38.896 g --> 38.9 g BaCl2
Answer: With the exception of hydrogen, all atoms have three main parts. The parts of an atom are protons, electrons, and neutrons. A proton is positively charged and is located in the center or nucleus of the atom. Electrons are negatively charged and are located in rings or orbits spinning around the nucleus.
Explanation:
A metal ion is a type of atom compound that has an electric<span> charge. </span>Such<span> atoms willingly lose electrons in order to build positive ions called cations.</span>
Answer:
protons and neutrons
Explanation:
those particles account for 99.99% of mass
