<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
Answer:
Atoms and matter
Explanation:
atoms are the building blocks and matter is everything
The answer is Al.
If it is a main group element with 3 electrons in its Lewis dot structure, it must be in group 3A. If it is in the 3p orbital section, then it must be in period 3, since the p orbital is a valence orbital and the number that preceeds it is the principal quantum number. Therefore, your answer is the element in period 3 and group 3A, which is aluminum.
Answer:
<h2>D. Krypton (Kr)</h2>
<u>Explanation:</u>
because
Neon and Krypton, both are belongs to Inert or Noble gas Group
Answer:
There are 3, 64 moles of NaCl.
Explanation:
First we calculate the mass of 1 mol of NaCl, starting from the atomic weights of Na and Cl obtained from the periodic table. Then we calculate themoles in 213 grams of NaCl, making a simple rule of three:
Weight NaCl= Weight Na + Weight Cl = 23 g + 35, 5 g= 58, 5 g/ mol
58,5 g ------1 mol NaCl
213 g---------x= (213 g x 1 mol NaCl)/ 58, 5 g= <em>3, 64 mol NaCl</em>