Answer:
D
Explanation:
Metallic character decreases as you move across a period in the periodic table from left to right. This occurs as atoms more readily accept electrons to fill a valence shell than lose them to remove the unfilled shell. Metallic character increases as you move down an element group in the periodic table. This is because electrons become easier to lose as the atomic radius increases, where there is less attraction between the nucleus and the valence electrons because of the increased distance between them.
If an atom gains an electron and gets a negative charge because of it, it is a negatively charge ion AKA an anion.
One mole of oxygen gas, which has the formula O2, has a mass of 32 g and contains 6.02 X 1023 molecules of oxygen but 12.04 X 1023 (2 X 6.02 X 1023) atoms, because each molecule of oxygen contains two oxygen atoms.
Answer:
The molar mass of the unknown substance is 255g/mole
Explanation:
Freezing point depression is given by
ΔT = i · Kf · m
Where
m = molality of the solute
i = van't Hoff's factor = i for non electrolyte
Kf = 20.4 °C/m = cryoscopic constant
ΔT = Freezing point depression
Therefore ΔT = 6.6 - 5 = 1.6 °C
1.6 °C = 20.4 °C/m × 1 × m
Therefore m = 1.6/20.4 = 0.0784 m
number of moles in 2.50 g of cyclohexane = 0.0784 m or 0.0784 moles of the substance in 1000 grams of cyclohexane. That is
2.5 ×0.0784/1000 moles in 2.5 graams of cyclohexane that is
1.96 × 10⁻⁵ moles in 2.5 grams of cyclohexane
1.96 × 10⁻⁵ moles of the substance weighs 0.050 grams
Therefore 1 Mole weighs (0.05 g)/(1.96 × 10⁻⁵ moles) = 255g/mole
Answer: p2 = 1.06p1
Explanation: pressure increases with temperature increase.
According to Gass law
P1/T1 = P2/T2
T1 = 20°c = 20 +273 = 293k
T2 = 40°c = 40 +373 = 313k
Therefore
P2 = P1T2/T1 = 313P2/293
P2 = 1.06P1