Answer:
D
Explanation:
the charges need to balence out
so finding the LCM which is 12 we find we need 3x's
and 4 zs
so that makes the formula X3Z4 which is D
Lo siento ... necesito puntos!......
conversion between mass and moles#
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<em>A substance's molar mass is calculated by multiplying its relative atomic mass by the molar mass constant (1 g/mol). The molar mass constant can be used to convert mass to moles. By multiplying a given mass by the molar mass, the amount of moles of the substance can be calculated.</em>
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Answer:
Option A. 70.0 KPa.
Explanation:
Data obtained from the question include:
Pressure (torr) = 525.4 torr
Pressure (kPa) =?
The pressure expressed in torr can be converted kPa as shown below:
760 torr = 101.325 KPa
Therefore,
525.4 torr = (525.4 x 101.325) / 760 = 70.0 KPa.
Therefore, 525.4 torr is equivalent to 70.0 KPa.
Mass of aspirin = 0.025 g
Molar mass of C9H8O4 is 180.1583 g/mol
moles of aspirin = .025g / 180.1583 g/mol = 0.000138767 moles
volume solution = .250 L
molarity of the solution = 0.000138767 moles / .250L =5.551 x 10 ^-04 Moles / liter
for aspirin i = Vant'Hoff factor = 1 particle in solution
T = 25 + 273 =298 K
osmotic pressure = M x R x T x i =
5.551 x 10 ^-04 mole L -1 x 0.08206 L atm K−1 mol−1 x 298 K x 1 = 0.0136 atmospheres
