1. Look at the atomic number of the element(located in upper left corner of the element box).This number represent the number of protons of the element.In same of the elements the number of electrons and protons are the same. in other (negative) you have to calculate
2. Look at the atomical mass( located underneath the element, which is a sum of neutrons and protons.Round the mass to the whole number and substract the atomic number. That will be number of neutrons.
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Pure substance element I think
Answer:
According to the proton theory of acids and bases by J. Brønsted and T. Lowry, the acid is<u> proton donor</u>.
Explanation:
According to the Bronsted lowry concept an acid is substance that gives protons or hydrogen ion while,
Base is substance that accept hydrogen ion or proton.
Consider the following example:
NH₃ + HCl → NH₄⁺ + Cl⁻
In this example HCl is Bronsted lowry acid it gives H⁺ while ammonia is Bronsted lowry base because it accept H⁺.
This also gives the concept of conjugate acid and base. In given example Cl⁻ is conjugate base of HCl while NH₄⁺ is conjugate acid of ammonia.
The balanced chemical reaction would be expressed as follows:
2Na + Cl2 = 2NaCl
We are given the amount of sodium metal to be used reaction. This would be the starting value for the calculations. We do as follows:
6.25 g ( 1 mol / 22.99 g ) ( 1 mol Cl2 / 2 mol Na ) ( 22.4 L / 1 mol ) = 3.045 L Cl2 needed
Hope this answers the question.
