I did this question before and the answer is Magnesium and silicon, B.
Answer:
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Explanation:
Volume of room = 
= 
Now, according to conversion factor, convert 6,400 mg to micrograms
Since, 1 mg is equal to 1000 microgram.
Therefore, 6,400 mg = 
= 6,400,000 micrograms of acetone.
To calculate concentration of acetone, divide volume and evaporated amount of acetone in micrograms.
Thus,
Concentration of acetone = 
= 39296.5910 microgram per cubic meter or 
Hence, concentration of acetone is equal to 
Answer:
13.2 g Na2CO3
Explanation:
Convert 10.0 g NaOH to mol.
10.0 g x 1 mol/39.997 g = 0.250 mol
Use mol ration given by the equation: 2 mol NaOH to 1 mol Na2CO3
0.250 mol NaOH x 1 mol Na2CO3/2 mol NaOH = 0.125 mol Na2CO3
Finally, convert the moles of Na2CO3 to grams.
0.125 mol Na2CO3 x 105.99 g/1 mol = 13.2 g
Answer: (e) The pressure in the container increases but does not double.
Explanation:
To solve this, we need to first remember our gas law, Boyle's law states that the pressure and volume of a gas have an inverse relationship. That is, If volume increases, then pressure decreases and vice versa, when temperature is held constant. Therefore, increasing the volume in this case does not double the pressure owning to out gas law, but an increase in pressure would be noticed if temperature is constant
