Prepare 250ml of a 4.8m nacl solution.

First we need to calculate the number of moles of NaCl in 250 ml of 4.8 M NaCl solution.

Number of moles = molarity × (volume of solution in L)

                             = (4.8 M) × (250/1000 L) = 1.2 moles

Now calculte the mass of NaCl required to be dissolved in 250 ml to prepare 4.8 M Nacl solution.

Hence, mass of NaCl = moles of NaCl ×molar mass of NaCl

                                   = 1.2 moles×58.5 g/mol = 70. 2 g

Thus, we need nto dissolve 70.2 grams of NaCl in 50 ml water and then dilute it to 250  ml to get the moalrity of 4.8 M.

answers: to make sure that all of the broken pieces of tablet were added to the water, to allow for fair comparison of all three trials, with different particle sizes to avoid experimental error

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explanation:

smoke is the matter of a gas