How many moles are 25.0 mL of benzene (density 0.876 g/mL)?

There are 0.281 moles of benzene.

Explanation:

The density (δ) is the ratio between mass and volume of a compound. We obtain the mass of benzene using the density formula, then we calculate the weight of 1 mole of benzene (C6H6).

δ=m/v--> m=δxV= 0,876 g/ml x 25, 0 ml= 21, 9 g

Weight 1 mol C6H6= 6x(Weight C)+ 6x(Weight H) = 6 x 12 g+ 6 x 1g=78g/mol

78 g1 mol C6H6

21,9gx= (21, 9 g mol x1 mol C6H6)/ 78 g= 0,28076923 mol

for step 7 table c on the lab "newtons law of action"   the average time it took the car to travel .25 meters   was 1.92 seconds.

the average time it took the car to travel 0.50 meters was 2.61 seconds

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