<h3><u>Answer;</u></h3>
As, & Sr --------[Kr]
Be ------------------- [He]
O, & Mg ----------[Ne]
S, & Ca -------------[Ar]
<h3><u>Explanation</u></h3>
- <u>The Be+ ion has 2 electrons, just like He. The ions Mg2+ and O2− each has 10 electrons like Ne. </u>
- <u>The S2− and Ca2+ each has 18 electrons like Ar. The ions As3− and Sr+ each have 36 electrons like Kr.</u>
- <u>Atoms of elements lose or gain electrons to attain a stable configuration which is equivalent to the configuration of noble gases.</u>
- When atoms lose or gain electrons they form ions, which are either positively charged or negatively charged. When atoms lose electrons they form positively charged ions while if they gain electrons the form negatively charged ions
Answer:
4.8 %
Explanation:
We are asked the concentration in % by mass, given the molarity of the solution and its density.
0.8 molar solution means that we have 0.80 moles of acetic acid in 1 liter of solution. If we convert the moles of acetic acid to grams, and the 1 liter solution to grams, since we are given the density of solution, we will have the values necessary to calculate the % by mass:
MW acetic acid = 60.0 g/mol
mass acetic acid (the solute) = 0.80 mol x 60 g / mol = 48.00 g
mass of solution = 1000 cm³ x 1.010 g/ cm³ (1l= 1000 cm³)
= 1010 g
% (by mass) = 48.00 g/ 1010 g x 100 = 4.8 %
If you cut the cube and keep all the pieces you are causing only physical change
<span>We breathe around an average of 500 ml of air in 1 normal (or relax) breathing. The lungs already have around 3 litres of reserve breathing. Since there is around 21% oxygen in air, we breathe in around 105 ml of Oxygen from the air. That is equal to around 0.14 g of Oxygen.</span>
The outer electron of atom B has moved to a higher energy state.<span>B - 1s2, 2s2, 2p6, 5s1 </span>
