When the concentration is expressed in molality, it is expressed in moles of solute per kilogram of solvent. Since we are given the mass of the solvent, which is water, we can compute for the moles of solute NaNO3.
0.5 m = x mol NaNO3/0.5 kg water
x = 0.25 mol NaNO3
Since the molar mass of NaNO3 is 85 g/mol, the mass is
0.25 mol * 85 g/mol = 21.25 grams NaNO3 needed
<span>299,792,458 meters per <span>second</span></span>
Answer:
Gaps are produced in the light spectra that correspond to wavelengths of absorbed photons.
Explanation:
When electrons in atoms absorb energy, they move from a lower energy level to a higher energy level. With time, they revert to the their original energy state emitting a photon of light of appropriate wavelength.
The absorbed photons do not show up in the spectrum. They appear as dark lines in the spectrum. Hence, the absorption spectrum is the exact inverse of the emission spectrum. The dark lines in the spectrum indicates that the colors that ought to occupied those points there have been absorbed.
Which of the following is not a disaccharide:
<span>d)</span>
Answer:
0.13 atm
Explanation:
Using the Ideal Gas Law; PV=nRT, we can rearrange to solve for pressure.
P=nRT/V
P is pressure, n is number of moles (0.023), R is a constant (0.08206 L*atm/mol*K), T is temperature in Kelvin (293.15K) and V is volume, 4.2 L.
So, plugging in;
P=(0.023mol)(0.08206L*atm/mol*K)(293.15K)/(4.2 L)
P=0.1317 atm
P=0.13 atm; multiply by 760 to get to Torr or mmHg.
