Answer:
A radionuclide is an atom that has excess nuclear energy, making it unstable. This excess energy can be used in one of three ways: emitted from the nucleus as gamma radiation; transferred to one of its electrons to release it as a conversion electron; or used to create and emit a new particle from the nucleus. Wikipedia
The existence of isotopes contradicts part of Dalton's original atomic theory because he said all atoms of a given element are identical have the same mass size and chemical properties.
1 mole of water = 18 grams (you can find this by finding mass of two hydrogen and one oxygen which is (1*2) + 16 = 18)
1.8 grams = 0.1 moles
1 H2O molecule has 10 electrons so 0.1 moles can be computed as:
(6.023*10^23)*(0.1)*10 = 6.023*10^23 electrons
False .... A neutral atom needs the same number of protons and electrons
Answer:
electronegativity of bonded atoms and shape.
Explanation:
if the shape of molecule is symmetric it will non polar. The polar molecules are trigonal in shape.
Sodium chloride is ionic compound. The electronegativity of chlorine is 3.16 and for sodium is 0.93. There is large difference is present. That's why electron from sodium is transfer to the chlorine. Sodium becomes positive and chlorine becomes negative ion and compound is polar.
Covalent bond:
It is formed by the sharing of electron pair between bonded atoms.
The atom with larger electronegativity attract the electron pair more towards it self and becomes partial negative while the other atom becomes partial positive and compound will polar.
For example:
In water the electronegativity of oxygen is 3.44 and hydrogen is 2.2. That's why electron pair attracted more towards oxygen, thus oxygen becomes partial negative and hydrogen becomes partial positive.