0.409 g!
Pls mark brainlest.!:)
Answer:
How is it possible that helium, having 2 protons, and lithium, having 3 protons, are so different in terms of their physical properties? How come one is a gas at room temperature and the other is a solid metal?
Then why lithium and beryllium, the latter having 1 proton more than the former, are both metals and solids at room temperature?
Now if you remove neutrons from the nuclei of any element (except hydrogen), they form isotopes that have similar chemical properties and different physical properties, while still being an atom of the same element - therefore the protons, if I understand it correctly, are what determine whether an element is a gas or a solid at room temperature, and not the neutrons (or even electrons). Is this true?
The deeper question is that why do the properties of elements and their atoms change significantly - in some cases as with helium and lithium - just by having an additional proton in their nucleus, if the fundamental building blocks of protons (quarks) are identical for each proton? Then in the case of lithium and beryllium, why is the change in physical properties so subtle compared to the first case?
Edit
This question has already been asked before, however I am specifically interested in helium and lithium - why is one a gas and the other a solid metal at room temperature, having completely different chemical and physical properties? Is this a result of the electron shell configuration? Why does an extra proton, neutron and electron give rise to such a difference?
Answer : The pH of the solution is, 3.37
Explanation : Given,
![pK_a=3.8](https://tex.z-dn.net/?f=pK_a%3D3.8)
Concentration of
= 0.3 M
Concentration of
= 0.8 M
Now we have to calculate the pH of solution.
Using Henderson Hesselbach equation :
![pH=pK_a+\log \frac{[Salt]}{[Acid]}](https://tex.z-dn.net/?f=pH%3DpK_a%2B%5Clog%20%5Cfrac%7B%5BSalt%5D%7D%7B%5BAcid%5D%7D)
![pH=pK_a+\log \frac{[HCOOK]}{[HCOOH]}](https://tex.z-dn.net/?f=pH%3DpK_a%2B%5Clog%20%5Cfrac%7B%5BHCOOK%5D%7D%7B%5BHCOOH%5D%7D)
Now put all the given values in this expression, we get:
![pH=3.8+\log (\frac{0.3}{0.8})](https://tex.z-dn.net/?f=pH%3D3.8%2B%5Clog%20%28%5Cfrac%7B0.3%7D%7B0.8%7D%29)
![pH=3.37](https://tex.z-dn.net/?f=pH%3D3.37)
Thus, the pH of the solution is, 3.37
Answer:
5.95 moles
Explanation:
No of moles = given mass / molar mass
No of moles = 137/23
= 5.95 moles
The balanced chemical equation between nitric acid and calcium hydroxide is:
2HNO3 (aq) + Ca(OH)2 (aq) ---> Ca(NO3)2 (aq) + 2H2O (l)
Calcium oxide has the chemical formula Ca(OH)2, while nitric acid has the formula HNO3. Salt (an ionic substance created by the reaction of an acid and a base) and water are the byproducts of the reaction between an acid and a base.
Now, to balance the equation, we have to make sure there are the same number of atoms (or ions) on both sides of the equation. Also, we must list the state of each compound in the equation.
HNO3 (aq) + Ca(OH)2 (aq) ---> Ca(NO3)2 (aq) + H2O (l)
We must balance the equation because the number of atoms on each side is not equal. To the right of the chemical formulas, put the balancing numbers.
The balanced chemical equation between nitric acid and calcium hydroxide has the equal amount of atoms on both sides as a result.
2HNO3 (aq) + Ca(OH)2 (aq) ---> Ca(NO3)2 (aq) + 2H2O (l)
Learn more about balanced chemical equation here:
brainly.com/question/28294176
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