Molecular mass of a substance at NTP?

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To determine the molecular mass of a substance that occupies a volume of 5.6 liters when vaporized at Normal Temperature and Pressure (NTP), it is essential to clarify that NTP refers to conditions of 20°C and 1 atm. The discussion highlights the importance of understanding standard conditions, contrasting NTP with Standard Temperature and Pressure (STP) and Standard Ambient Temperature and Pressure (SATP). The molecular mass can be calculated using the ideal gas law, where 1 mole of gas occupies 22.4 liters at STP, but under NTP conditions, the volume occupied by 1 mole is approximately 24.45 liters. Given the volume of 5.6 liters, the molecular mass can be derived from the relationship between the volume, temperature, and pressure, leading to the conclusion that the molecular mass of the substance is likely to be one of the provided options: M, 2M, 3M, or 4M.
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M g of a substance when vapourised occupy a volume of 5.6L at NTP, molecular mass of the substance will be?

Here, what does the NTP refer to [normal temperature pressure?]
options are
M, 3M, 2M, 4M
 
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xiphoid said:
Here, what does the NTP refer to [normal temperature pressure?]

i guess so

from http://www.engineeringtoolbox.com/stp-standard-ntp-normal-air-d_772.html

STP - Standard Temperature and Pressure
STP is commonly used to define standard conditions for temperature and pressure which is important for the measurements and documentation of chemical and physical processes:

  • STP - Standard Temperature and Pressure - is defined by IUPAC (International Union of Pure and Applied Chemistry) as air at 0°C (273.15 K, 32°F) and 105 pascals
  • STP - commonly used in the Imperial and USA system of units - as air at 60°F (520 °R) and 14.696 psia (15.6°C, 1 atm)
Note that the earlier IUAPC definition of STP to 273.15 K and 1 atm (1.01325 105 Pa) is discontinued.

1 Pa = 10-6 N/mm2 = 10-5 bar = 0.1020 kp/m2 = 1.02x10-4 m H2O = 9.869x10-6 atm = 1.45x10-4 psi (lbf/in2)

NTP - Normal Temperature and Pressure
NTP is commonly used as a standard condition for testing and documentation of fan capacities:

  • NTP - Normal Temperature and Pressure - is defined as air at 20°C (293.15 K, 68°F) and 1 atm (101.325 kN/m2, 101.325 kPa, 14.7 psia, 0 psig, 29.92 in Hg, 760 torr). Density 1.204 kg/m3 (0.075 pounds per cubic foot)
SATP - Standard Ambient Temperature and Pressure
SATP - Standard Ambient Temperature and Pressure is also used in chemistry as a reference:

  • SATP - Standard Ambient Temperature and Pressure is a reference with temperature of 25°C (298.15 K) and pressure of 101 kPa.
 
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