-- Find the mass of all the pieces before the reaction.
-- Find the mass of all the pieces after the reaction.
-- Find the difference . . . (mass before) minus (mass after)
-- If any mass is missing, either you lost track of it, or else
it was converted to energy.
How much energy ?
(the missing mass) times c² .
The answer is B. because NaCl are just two elements with one atom from each element
Answer:
C
Explanation:
Light with energy above a certain point can be used to knock electrons loose, freeing them from a solid metal surface, according to Scientific American.
photoelectric effect is the emission of electrons when electromagnetic radiation, such as light, hits a material
<span>320. seconds
The ideal gas law is
PV = nRT
where
P = pressure of the gas
V = volume of the gas
n = number of moles of the gas
R = the ideal gas constant
T = absolute temperature of the gas.
Since we're going to want the volume, solve for V
PV = nRT
V = nRT/P
755 mmHg converts to 100658.11 Pascals
25 C = 298.15 K
Let's calculate nT/P, then we'll multiply by R
1 mol * 298.15 K / 100658.11 Pa = 0.002962007 K mol/Pa
The value for R in the most convenient units is 8.3144598 m^3 Pa/(K mol), so
0.002962007 K mol/Pa * 8.3144598 m^3 Pa/(K mol) = 0.024627486 m^3
So 1 mole of air at the specified temperature and pressure has a volume of 24.627 liters. The rest of the problem is now trivial. Just divide by the rate of consumption, so
24.627 l / 0.0770 l/s = 319.8374798 s
Rounding the result to 3 significant figures gives 320. seconds.</span>
