Primary Standard Solutions (HSC SSCE Chemistry): Flashcards
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Primary standard definition
Primary standard definition
Substance for solution with accurately known concentration
Accuracy in chemistry
Accuracy in chemistry
Number of significant figures in a measurement
Why primary stds need large molar mass
Why primary stds need large molar mass
Larger masses reduce percentage error, improving accuracy
Why primary stds must be anhydrous
Why primary stds must be anhydrous
Water of hydration varies with humidity, altering composition
Why primary stds must be stable in air
Why primary stds must be stable in air
Won't react with , , or atmospheric moisture
Most common primary std in school labs
Most common primary std in school labs
Anhydrous sodium carbonate ()
Second common primary std
Second common primary std
Sodium hydrogen carbonate ()
Why can't be a primary std?
Why can't be a primary std?
Hygroscopic and reacts with from air
Why not use ?
Why not use ?
Contains water of hydration that varies with humidity
Why rinse beaker during preparation?
Why rinse beaker during preparation?
To transfer all weighed substance to volumetric flask