A mixture of gases with a pressure of 900 mm Hg contains 20% of oxygen and 80% of nitrogen by volumeWhat is the partial pressure of the oxygen gas in the mixture? A-45mmHg
B-180mmHg
C-210 mmHg
D-320 mmHg

180 mmHg

Explanation:

Total volume of gases = 20% + 80%= 100%

Total pressure of gases = 900 mm Hg

Note that partial pressure of a gas = mole fraction × total pressure

Mole fraction of oxygen = 20/100

Hence partial pressure of oxygen= 20/100 × 900 mm Hg

partial pressure of oxygen= 180 mmHg

answer:

technetium is the most reactive. this is followed by silver. the least reactive out of these three elements is strontium.