The red diamond represents the potential hazards that are associated with the product.
<u>Answer:</u> The mass of sulfur dioxide gas at STP for given amount is 16.8 g
<u>Explanation:</u>
At STP conditions:
22.4 L of volume is occupied by 1 mole of a gas.
So, 5.9 L of volume will be occupied by = 
Now, to calculate the mass of a substance, we use the equation:

Moles of sulfur dioxide gas = 0.263 mol
Molar mass of sulfur dioxide gas = 64 g/mol
Putting values in above equation, we get:

Hence, the mass of sulfur dioxide gas at STP for given amount is 16.8 g
You answer this by using the pH formula and and the relation of pH and pOH, pH = -log[H+] and 14 = pH + pOH. The correct classification are as follows:
<span>A. [H2O+]=6.0x10^-12
basic
B. [H3O+]=1.4x10^-9
basic
C. [OH-]=5.0x10^-12
acidic
D. {OH-]=3.5x10^-10
acidic
Hope this answers the question.
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