The atomic mass of an element is the number of times of an atom of that element is heavier than an atom of carbon taken as 12. In simpler way, atomic mass is number of protons present in nucleus of an atom, which is a characteristic of an chemical element and is determines place of the element in the periodic table. Mass number is total number of protons and neutrons. If an uncharged atom looses electron from its outermost shell, it becomes cation, which is positively charged species. Atomic number and mass number do not change if electron goes out of an atom.
Uncharged copper after loosing two electrons is converted to 
which can be represented as follows:
→
Answer:
Number of moles = 0.057 × 10⁻⁷ mol
Explanation:
Given data:
Mass of SiO₂ = 3.4 × 10⁻⁷ g
Number of moles = ?
Solution:
Number of moles = mass/molar mass
Molar mass of SiO₂ = 60 g/mol
by putting values,
Number of moles = 3.4 × 10⁻⁷ g / 60 g/mol
Number of moles = 0.057 × 10⁻⁷ mol
Answer:
it readily gains another electron. the outer electron shell is closer to the nucleus, than iodine for example, which makes it less shielded (greater attraction for another electron = violent reaction to get it)
Explanation:
Explanation:
A non-electrolyte is defined as a solution which does not contain any ions and hence, it is unable to conduct electricity.
For example, when a non-polar substance like 
is dissolved in water then it will not dissociate into ions.
As electricity is the flow of ions or electrons. So, a non-electrolyte solution is not able to conduct electricity.
Similarly, a compound that is insoluble in water will not dissociate into ions. Hence, this type of solution will not be able to conduct electricity.
The accuracy is associated with magnitude of fractional error or relative error in that measurement
the precision of a measurement is associated with least count of the measuring instrument.
precision does not mean accuracy but both are highly demanded while making measurements in physics.
