Particles below the surface of a liquid
Answer:
<h2>
total no. of electron present in Valency shell is called valency electron </h2><h2>___________________</h2>
<h2>valency shell is that in which last electron is present</h2>
Answer:
Dalton expressed his assumption in A Modern Model of Chemical Theory that atoms of various elements should be uniformly differentiated, based on their differing atomic weights. In doing so, he became the first scientist to explain atom behavior as regards weight measurement.
Explanation: