be very reactive and will attack ozone
be non-reactive and will not attack ozone
not change the level of ozone in the atmosphere
increase the level of ozone in the atmosphere
Correct answer is A
CFCs (Chlorofluorocarbons) have a lifetime in the atmosphere of about 20 to 100 years, and consequently one free chlorine atom from a CFC molecule can do a lot of damage, destroying ozone molecules for a long time
Which of the following separation techniques can be employed in obtaining solvent from its solution?
Evaporation
Distillation
Filtration
Precipitation
Correct answer is B
Distillation is the process of separating the components or substances from a liquid mixture by using selective boiling and condensation.
boiling the water
adding excess calcium hydroxide
adding a calculated amount of calcium hydroxide
adding sodium carbonate
Correct answer is D
Its D because when sodium carbonate reacts with calcium hydrogentrioxocarbonate it gives sodium hydrogentrioxocarbonate and calcium trioxocarbonate. However, when it react with calcium sulphate, calcium carbonate and sodium tetraoxosulphate is formed
In the removal of water hardness, permutit is regenerated with a strong solution of
NaOH
Na\(_3\)SO\(_4\)
Na\(_3\)CO\(_3\)
NaCl
Correct answer is D
permutit water softener can be regenerated by washing the spent resin with brine( saturated sodium chloride solution). The solution ions replace the calcium or magnesium ions present in it.
\(CaR_{2(s)}\) + 2\(NaCl_{aq}\) → \(CaCl_{2(aq)}\) + 2\(NaR_{2(s)}\)
disintegration
polymerization
cracking
degradation
Correct answer is C
Cracking is the breakdown of a large alkane into smaller, more useful alkenes. Simply put, hydrocarbon cracking is the process of breaking a long-chain of hydrocarbons into short ones. This process might require high temperatures and high pressure.