All of the the answers are are correct but a fume hood is more for if you are dealing with chemicals that can produce fumes the are deadly to people
<u>Analysing the Question:</u>
We are given a 250 mL solution of 0.5M K₂Cr₂O₇
Which means that we have:
0.5 Mole in 1L of the solution
0.125 moles in 250 mL of the solution <em>[dividing both the numbers by 4]</em>
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<u>Mass of K₂Cr₂O₇ in the given solution:</u>
Molar mass of K₂Cr₂O₇(Potassium Dichromate) = 194 g/mol
<em>we know that we have 0.125 moles in the 250 mL solution provided</em>
Mass = Number of moles * Molar mass
Mass = 0.125 * 194
Mass = 36.75 grams
2Mg+ O₂= 2MgO
The charge of Mg is+2 and the charge of Oxygen is -2. 2 oxygen atoms will have a charge of -4 so the Mg atoms have to equal +4. A coefficient of 2 for the Mg atoms will balance it out
Mass of block, m = 5.26 lb
1 lb = 453.592 g
5.26 lb = 2385.896 g
V = 14 in3
1 in = 2.5 cm
1 in3 = 15.625 cm3
14 in3 = 218.75 cm3
Density = mass/volume
= 2358.896 / 218.75
= 10.783 g/cm3