Answer:
A population or community research line can be carried out, wherever at a certain point in time, regardless of whether it is a cross-sectional study.
In addition, the people who would be the population to be studied or the object of study might or might not know the cause of the study (blind) while the researcher could be experimentally participatory.
Explanation:
They are prevalence studies, in which the presence of a health condition or state is determined in a well-defined population and in a determined time frame: one day, one week, a particular moment in life, even if it does not temporarily coincide in all the subjects (for example, the blood pressure figures at the time of entering the school or at the beginning of the holidays, the prevalence of diabetes in hospitalized patients on a given day, etc.).
They are like "photographs" of a state of affairs at a given moment. The simultaneous determination of what is understood by exposure and event does not allow defining causality.
2Al +3CuSO4=Al2 (SO4)3+3Cu.
is the balanced equation.
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A pH scale runs from 1 to 14 with 7 being neutral.
1-6 has base like properties
8-14 has avid line properties
since this solution has a pH scale of 4.... the solution is basic
The a mixture of 4-tert-butylphenol and 2- chlorobenzoic acid is separate by the by using bicarbonate solvent.
When solution of bicarbonate is added in mixture of 4-tert-butylphenol and 2- chlorobenzoic acid then 2- chlorobenzoic acid form a carboxylate ion whereas 4-tert-butylphenol is underacted and filtered out.
Since, only 2- chlorobenzoic acid which is acid is convert into its conjugate base by solution of bicarbonate in mixture of 4-tert-butylphenol and 2- chlorobenzoic acid .
However, phenol is less acidic than carboxylic acid. Both phenol and carboxylic acid is soluble in organic solvent . At that point as the phenol isolates as an oil, one needs to cool the blend in an ice shower to encourage crystallization
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