There are 11 electrons in Sodium(Na)
The first shell can hold 2 electrons
The second shell can hold 8 electrons
The third shell can also hold 8 electrons but there is only 1 left
so the answer is 2, 8, 1
In 1803AD, Osmium was discovered by Smithson Tennant when dissolving an impure sample of platinum in aqua regia, a mixture of hydrochloric and nitric acids. He was able to determine that the black powder left behind after dissolving the platinum was actually a mixture of two new elements, indium and osmium.
•Osmium is a bluish-white and shiny metal.
•Osmium is very hard and is brittle even at very high temperatures.
•Osmium has the lowast vapor pressure and the highest melting point among the platinum group of metals.
•Osmium's density is slightly more than iridium hence is credited as the heaviest element.
The answer is Na < Cl
Chlorine is more electronegative than sodium because this follows the trend of the periodic table. The trend states that an element's electronegativity increases from left to right of a period and bottom to up of a group. Since sodium and chlorine are from the same period, and chlorine is at the right of sodium, chlorine is more electronegative.
Mol= mass (grams) /Mr
Mr of Sulfuric Acid (H2SO4): 98
mol= 329/98
=3.36 moles
To calculate atomic mass, you have to take to weighted average of the isotopes' masses. What that means is M = RA*106 + (1 – RA)*104, where RA is relative abundance expressed in decimal form. If you simplify the right side of that equation, you get M = 2*RA + 104. Doing a little more algebra yields RA = (M –104)/2 = (104.4 – 104)/2 = 0.4 / 2 = 0.2, which is 20%. So the answer is B.