Answer:
- second choice:<em><u> 1.0 g of the solution contains 15 × 10⁻⁶ g of benzene.</u></em>
Explanation:
ppm is a unit of concentration that means parts per million. In grams that is grams of solute per one million (10⁶) grams of solution.
Then, <em>15 ppm of benzene</em> means that there are 15 grams of benzen in 1,000,000 grams of solution.
That leads to:
- 1,000,000 g solution / 15 g benzene
Multiplying numerator and denominator by 10⁻⁶ you find:
- 1,000,000 × 10⁻⁶ g solution / (15 × 10⁻⁶ g benzene)
Simplifying:
- 1.0 g solution / (15 × 10⁻⁶ g benzene)
Which is read as 1.0 g of the solution contains 15 × 10⁻⁶ g of benzene, i.e. the second answer choice.
Answer:
Explanation:
The glass (which does not crystallize even though it is accepted) of a window is NOT a mineral, since it is neither a substance of natural origin (although it is manufactured from natural components) nor does it have a defined crystalline structure, that is, the atoms they are not arranged in an orderly and regular way along axes and planes forming flat faces that keep a symmetry.
Remember that a mineral is defined as a solid, inorganic, homogeneous substance, of natural origin, with a crystalline structure and a determined and well-defined chemical composition within narrow margins and that has regular and characteristic physical properties.
Answer:
final pressure ( P2) = 467.37 mm Hg
Explanation:
ideal gas:
∴ P1 = 570 mm Hg * ( atm / 760 mm Hg ) = 0.75 atm
∴ T1 = 25 ° C = 298 K
∴ V1 = 1.250 L
∴ R = 0.082 atm L / K mol
⇒ n = P1*V1 / R*T1
⇒ n = (( 0.75 ) * ( 1.25 )) / (( 0.082 ) * ( 298 ))
⇒ n = 0.038 mol gas
∴ T2 = 175 °C ( 448 K )
∴ V2 = 2.270 L
⇒ P2 = nRT2 / V2
⇒ P2 = (( 0.038 ) * ( 0.082 ) * ( 448 )) / 2.270
⇒ P2 = 0.615 atm * ( 760 mm Hg / atm ) = 467.37 mm Hg
The chemical formula for ammonia is NH3. So first, you need to find the molar mass of ammonia (how many grams in one mole).
N=14g
H3=3g
So one mole of NH3 is 17 grams, you can divide 82.9 grams by 17 grams to find the number of molecules. The answer should be 4.876 moles (molecules) of ammonia. Hope this helps!
Answer:
Radiation is the transfer of thermal energy by waves that can travel through empty space. When the waves reach objects, they transfer thermal energy to the objects.