The mixture does not maintain a uniform composition. A homogeneous mixture really is the same anywhere you sample it, while sand generally settles out of water when given the chance and there's likely more sand at the bottom than at the top.
<span>Eukaryota Cells have to Preform: Organelles.</span>
By use of ideal gas equation PV= nRT where n is the number of moles,P = pressure, V = volume, R= gas constant (0.08206 L. atm/ mol.k) ant T is the temperature,
to calculate the number of moles(n) =PV/RT
convert ml to L, that is 200/1000= 0.2 L
convert mmHg to atm, that is 780mm hg x 1atm/ 760 mm hg= 1.026 atm
convert temperature to kelvin, that is 135 +273= 408 k
n is therefore= (0.2 x 1.026)/ ( 0.08206 x 408)= 6.129 x10^-3 moles
from avogadro constant 1moles = 6.02 x10^23 molecules what about 6 .129 x10^-3 moles
= ( 6.02 x10^23) x (6.129 x10^-3)/ 1mole = 3.69 x10^21 molecules
The correct option is D.
In chemistry, a pure substance refers to a matter that possesses definite and constant composition with unique chemical properties. Another word for a pure substance is chemical substance. A pure substance typically contains only one type of atom or only one type of molecule. Examples of pure substances are water, sodium chloride, gold, silver, etc. In the question given above, we are told that the unknown element can only be broken down by chemical mean, this shows that the unknown compound is a chemical compound.
Answer: 1M
Explanation:
Molarity = mols/L
moles of lead bromide: 183.51/ 367.0 = 0.5 mol
500 ml/ 1000 mL = .5L
.5 mol / .5 L = 1 mol/L = 1M
