11. (2 points) A metallic rectangular block measures 2.00 cm by 3.00 cm by 4.50 cm. If its density is 11.34 g/cm?, what is the mass of this metallic rectangular block? (Hint: D = m/] A. B. C. 0.420 g 15.7 g 27.0 g 306 g D.

Agas mixture with a total pressure of 745 mmhg contains each of the following gases at the indicated partial pressures: co2, 245 mmhg ; ar, 119 mmhg ; and o2, 163 mmhg . the mixture also contains helium gas. part a what is the partial pressure of the helium gas? phe p h e = nothing mmhg request answer part b what mass of helium gas is present in a 10.2-l sample of this mixture at 283 k ? m m = nothing g request answer

Describe the chemical reaction based on the chemical equation below. also, explain whether the equation is balanced.

Aroom with dimensions 7.00m×8.00m×2.50m is to be filled with pure oxygen at 22.0∘c and 1.00 atm. the molar mass of oxygen is 32.0 g/mol. how many moles noxygen of oxygen are required to fill the room? what is the mass moxygen of this oxygen?