Question 17
The subscript 2 is the atomic number for helium and subscript 4 is the mass number for Helium
<u><em>explanation</em></u>
when writing down an isotope of an element the mass number of that isotope is written in upper side of the chemical symbol, while atomic number is written on the lower side.
Since 4 is on upper side it is the mass number of He, while 2 is the atomic number since it is on lower side.
Question 18
The type of radiation emitted when polonium -212 form lead 208 is an alpha particle
<u><em>explanation</em></u>
Alpha decay is a decay in which an atomic nuclei emit an alpha particles and be transformed into different atomic nuclei with a mass number that is reduced by 4
polonium 212 is reduced by 4 to form lead 208 therefore it undergo alpha particle decay.
Answer:
b
Explanation:
orbital overlap electron densities.
The answer of the given question above would be option C. Based on the example of a Hertzsprung-Russell diagram that is shown, what can we say about white dwarfs is that, they are <span>relatively dim or faint, but very hot. Hope this answers your question. Have a great day ahead!</span>
From the calcuation, the percent ionic character of the bond is 70%
<h3>What is percent ionic character?</h3>
The term percent ionic character has to do with the degree of ionic bonding that is contained in a compound. It can be estimated from the electronegativity of each element.
We can use the formula; 100(1 - e^(-ΔEN² / 4))
EN = χB − χA * 100/1
EN = 3.5 - 1.5 = 1
100(1 - e^(-1)^2/4)
= 70%
Learn more about percent ionic character:brainly.com/question/7034446
#SPJ1