I believe it's helium at 0.49 A
They have used added new elements to the table .
<u>Explanation:</u>
As new elements are discovered chemists add them to the period table leading to the periodic table undergoing continuous modifications. When the first periodic table in the world was formed, very few elements were known to humankind. Earlier periodic tables thus contain lesser number of elements than the modern ones.
Mendeleev's periodic table contained 63 elements arranged in the increasing order of their atomic masses. Modern periodic tables have far more number then the older ones like that of Mendeleev's and the elements are arranged in the order of their atomic numbers.
I will show you a method to find a velocity of anything:-
Find average velocity when acceleration is constant.
Set up an equation with position and time instead.
Find the distance between the start and end points.
Calculate the change in time.
Divide the total displacement by the total time.
Solve problems in two dimensions.
Answer:
0.497 moles/L
Explanation:
The reaction that takes place is:
- C₃H₆O₃ + NaOH → C₃H₅ONa + H₂O
First we c<u>alculate the moles of lactic acid in 0,821 g</u>, using its molar mass:
- 0,821 g ÷ 90 g/mol = 9,122x10⁻³mol lactic acid
<em>One mole of lactic acid reacts with one mole of sodium hydroxide</em> (it is a monoprotic acid), so in 18,34 mL of NaOH solution there are 9,122x10⁻³moles of NaOH:
- 18.34 mL ÷ 1000 = 0,01834 L
- 9,122x10⁻³mol ÷ 0,01834 L = 0.497 moles/L
Answer:
I do experiment with salicylic acid
Explanation:
I I think you have to run and write the equation that you made in salicylic acid because salicylic acid is very harmful to us human have skin that is made up of Cleveland Clinic