Which technique is preferred for delivering a solid into a pre- weighed beaker for weighting?

Question

here is the answer choices:

a. transfer more fo the reagent than is needed to the beaker. Return the excess to the bottle with a spatula.

b. Transfer the desired amount of solid from the reagent bottle by holding the necl of the open bottle over the beaker and tapping the bottle. Then weigh the beaker and solid

c. Weigh a spatula, scoop the desired amount of solid from the bottle, transfer it to the beaker and reweigh the spatula

d. weight a piece of filter paper, tap the neck otf the bottle too transfer solid to the filter paper, weigh the filter paper and transfer the solid tot he beaker

Answer 1

definitely d

you get an accurate amount weighed and you can deduct any mass of residue which stays on the paper

using a spatula vs tapping the neck of the bottle would be preferable though

Answer 2

I never pre-weighed beakers (too heavy).

I used special non-stick papers, placed on pan in balance, then carefully placed solid on the weighing paper until desired weight was reached, then carfully picked up paper, curled it, and poured solid into suitable container. If a solution was made, then I used a squirt bottle with water in it, and made sure the paper was cleaned. If no solution needed, then I looked at paper to make sure all solid was transferred.

I used a clean spatula during the weighing to transfer the solid.

Answer 3

D is the right answer. A is bad practice, you should never return anything to the bottle. B might work in a pinch if there's no filter paper, but it's generally not done either. C doesn't really do anything because you're weighing the same empty spatula twice.