When we see a rainbow, we are actually seeing colors of different wavelengths : mainly, red orange yellow green blue indigo and violet (in descending order of their wavelengths.)
Answer:
relative humidity
Explanation:
Relative humidity can be measured with a hygrometer
Ammonia is the compound NH3
2 Al + 6 HCl → 2 AlCl₃ + 3 H₂ (single displacement)
Ca + Br₂ → CaBr₂ (synthesis)
4 NH₃ + 5 O₂ → 4 NO + 6 H₂O (combustion)
2 NaCl → 2 Na + Cl₂ (decomposition)
FeS + 2 HCl → FeCl₂ + H₂S (double displacement)
single displacement - is a chemical reaction of the following type: A + BC → AC + B
double displacement - is a chemical reaction of the following type: AB + CD → AC + BD
synthesis - the chemical product is obtained by combining in a synthesis the constituent elements
combustion - usually a exothermic reaction of a particular compound with oxygen
decomposition - degradation of a compound in simpler elements
The answer for this question is D.