Answer:
Unit
Explanation:
Unit is used to describe how data is measured.
Answer:
the correct option is option c, I and IV
Explanation:
Atomic emission spectroscopy is used to determine quantity of element in a sample.
Atomic emission spectroscopy based on occurring of atomic emission when a valence electron from higher energy orbital comes back to lower energy orbital.
Light intensity emitted by a flame, plasma, arc of particular wavelength are used to excite the valence electron.
The intensity of atomic emission lines are proportional to number of atoms present in the excited state.
Emission intensity is affected by temperature of the excitation source and the efficiency of atomization.
Increase in temperature does not affect the ground state population.
Therefore, statements I and IV are correct.
So, the correct option is c.
Answer:
See Explanation
Explanation:
A decreasing temperature indicates that the dissolution process for the ammonium chloride requires input of energy from surroundings. That is, the process is essentially 2 parts => system (object of interest - NH₄Cl) and the surroundings (everything else - solvent - H₂O). The surroundings (water) solvent is showing a <u>measured</u> decrease in temperature or loss of energy (exothermic to surroundings) which flows into the system (NH₄Cl) and effects dissolution of salt into solution (endothermic to system).
One kilogram is equal to one thousand grams. Further, one gram is equal to 1000 mg. The conversion is as shown below,
(6.285 x 10³ mg) x (1 g / 1000 mg) x (1 kg / 1000 g)
The numerical value of the operation above is 0.006285 kg.
Filtration is a method for separating an insoluble solid from a liquid.