At a pressure of 780.0 mmHg and 25.2 C, a certain gas has a volume of 350.0 mL. What will be the volume of this gas under STP

The volume will be 0,330 L (330 ml).

Explanation:

We use the gas formula, which results from the combination of the Boyle, Charles and Gay-Lussac laws. According to which at a constant mass, temperature, pressure and volume vary, keeping constant PV / T. The conditions STP are 1 atm of pressure and 273 K of temperature. We convert the unit Celsius into Kelvin, the volume in ml into L and the pressure in mmHg into atm:

0 ° C = 273K, 25,2= 273 + 25, 2= 298,2K ;  350/1000= 0,350 L

760 mmHg1 atm

780 mmHgx= (780 mmHgx 1 atm)/760 mmHg=1, 03 atm

P1xV1/T1= P2xV2/T2

V2 =((P1xV1/T1)xT2)/P2

V2=((1, 03 atmx 0,350 L/298,2K)x273K)/1 atm= 0,330 L

"among the transition metal elements, manganese and zinc have a slight lowering of electronegativities. the reason behind this is that the nuclear charges of these elements are slightly weaker than the other transition metal elements due to the way their valence electrons are filled up. both manganese and zinc have their valence electrons filled up to the 4th shell with 1 pair of electrons (4s2) completely occupying it. although the electrons in the 3rd shell (3d) are yet to be paired since the outer most shell is filled up, the ability of the nucleus to attract electrons is lessened. hence,   the electronegativity (or the ability to attract electrons) is lessened."