Under the same conditions, 1 liter of gas has the greatest mass? a) Н2S b) CO2 c) Fe2O3 d) CO

In order to find out, you need to add up the molar masses of all atoms in the molecule. The molar mass of each chemical element is indicated in the periodic table on the right under the serial number, measured in grams / mol. For example, H2S: the molar mass of hydrogen is 1, sulfur is 32 (rounded to a whole number). We have 2 hydrogen, so the molar mass of H2S = 1+ 1+ 32 = 34 g / mol. CO2 = 12+ 16 + 16 = 44. Fe2O3 = 56 + 56 + (16 * 3) = 152. CO = 12+ 16 = 28. It is obvious that the molar mass of Fe2O3, equal to 152, is the largest.
Answer B) Fe2O3.