Question

STP conditions are:
a.) ${ 273K }, { 760 }$ mm of Hg
b.) ${ - 273K }, { 760 }$ mm of Hg
c.) ${ - 273K }, { 1 }$ mm of Hg
d.) ${ 273K }, { 1 }$ mm of Hg

Answer 1

Hint: STP means Standard Temperature and Pressure conditions. These standards have been set by IUPAC (International Union of Pure and Applied Chemistry).

Complete answer:
For STP conditions, the temperature is ${ 273K }$ and ${ 0 }^{ \circ }{ C }$ and pressure is ${ 1 }$ atm or ${ 760 }$ mm of Hg.
STP is the “standard” conditions that are used for measuring gas density and volume.
So, the correct option is A.

Additional Information:
Importance of STP
These are important for the expression of fluid flow rate.
Volumes of liquids and gases are highly dependent on temperature and pressure.
It is commonly used when standard state conditions are applied to calculations.
Equal volumes of gases contain equal numbers of gas particles if the temperature and pressure are the same.
STP is different from NTP which stands for Normal Temperature and Pressure.
STP is set by IUPAC as ${ 0 }^{ \circ }{ C }$ and ${ 100kPa }$ or ${ 1 }$ bar whereas NTP is set at ${ 101.325kPa }$ but uses ${ 20 }$ degree celsius as the temperature.
For an ideal gas, ${ V }_{ molar } = { 22.4L }$.
For a real gas, ${ V }_{ molar }$ depends on the constants ‘a’ and ‘b’.

Note: The possibility for the mistake is that you can choose the option (d). Standard pressure is ${ 1 }$ atm, not ${ 1 }$ mm. Also, you may confuse between option (b) as the standard temperature is ${ 273K }$ not ${ -273K }$. So, do not confuse among these options.