Answer: Noble gas configuration is the ionisation of valence electrons using the octet rules.
Explanation:
Noble gases are the halogen, iodine etc. they form molecules using anion valence electrons in order build octet structures.
The answer is: Dividing the number of molecules in the sample by Avogadro's number.
The Avogadro’s number is the number of atoms in 12 grams of the isotope carbon-12 (¹²C).
Na is Avogadro number or Avogadro constant (the number of particles, in this example carbon, that are contained in the amount of substance given by one mole).
The Avogadro number has value 6.022·10²³ 1/mol in the International System of Units; Na = 6.022·10²³ 1/mol.
For example:
N(Ba) = 2.62·10²³; number of atoms of barium.
n(Ba) = N(Ba) ÷ Na.
n(Ba) = 1.3·10²⁴ ÷ 6.022·10²³ 1/mol.
n(Ba) = 2.158 mol; amount of substance of barium.
<span>2.70x10^7 pm^3
We will assume that the sodium atom closely approximates a sphere. So the expression for the volume of a sphere is
V = 4/3 pi r^3
V = 4/3 pi (186 pm)^3
V = 4/3 pi 6434856 pm^3
V = 26954261.78 pm^3
Round to 3 significant figures, giving 2.70x10^7 pm^3</span>
Like most liquids, mercury expands, or gets bigger, when heated. As the environment gets warmer, the expanding mercury inside the narrow glass tube of the thermometer has nowhere to go but up. When the temperature cools, the mercury slides back down the tube.
Answer:
See below.
Explanation:
The mass of octane in the sample of gasoline is 0.02851 * 482.6 = 13.759 g of octane.
The balanced equation is:
2C8H18(l) + 25O2(g) ----> 16CO2(g) + 18H2O(g)
From the equation, using atomic masses:
228.29 g of octane forms 704 g of CO2 and 324.3 g of H2O
So the mass of CO2 formed from the combustion of 13.759 g of octane = (704 * 13.759) / 228.29
= 42.43 g of CO2.
Amount of water = 324.3 * 13.759) / 228.29
= 19.55 g of H2O.