(Answer) (d) Chemical reaction rates vary with the conditions of the reaction, but nuclear decay rates do not.
Rate of a chemical reaction refers to rate of formation of products from reactions during a chemical reaction. The rates of chemical reactions depend on various factors such as temperature, pressure, concentration of reactants, presence of catalyst etc. For this reason, chemical reaction rates vary with the conditions of the reaction.
Nuclear decay rate refers to the constant ratio of the number of atoms of radioactive nucleus that decay during a certain interval of time to the total number of radioactive atoms at the beginning of the time interval. Nuclear decay rates are constant and do not vary with the conditions of the reaction.
<span>Molarity is expressed as the number of moles of solute per volume
of the solution while molality is expressed as the number of moles solute per
mass of solution. We calculate as follows:</span>
5.74 mol / kg (1.238 kg/L) = 7.10612 mol / L or 7.11 M
The characteristics flame test color of metal ions are because of the atomic emission spectra.
When an atom absorbs a particular wavelength radiation, the electrons within it, move from lower energy level to the higher level of energy. Such a procedure is called absorption. When this stimulated electron to come back to its ground state, it loses energy in particular color on the basis of the frequency of the absorbed radiation. Such a procedure is called emission.
As an atom exhibit, distinct levels of energy, the level close to the nucleus possess less energy in comparison to the level, which is far from the nucleus. So, electrons move from lower energy level to the higher level by attaining particular energy, and after excitation, it comes back from high energy level to a low energy level with the emission of light.
According to Planck's concept, there is a specific difference of energy between the two energy level, so such energy difference is quantized. Only those radiation are absorbed, which are equivalent to the difference of energy between the two levels.
That is actually physics because it talks about motion.