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2 years ago

What is the density of an object whose mass is 142.5 g and whose volume is 7.5 mL?

Chemistry

2 answers:

rosijanka [135]2 years ago

8 0

D=19 mL hope this helps

guajiro [1.7K]2 years ago

6 0

Answer:

19g/mL

Explanation:

D=m/v

D=142.5/7.5

D=19 g/mL

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Answer:

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Explanation:

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Among the four species in this reaction, $\rm C_3H_8$ is species with the largest number of atoms per molecule. Assume that the coefficient of this compound is $1$ .

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By the conservation of atoms, the number of atoms on the right-hand side of the reaction should match those on the left-hand side. In this reaction, $\rm CO_2$ is the only product with carbon atoms, whereas $\rm H_2O$ is the only product with hydrogen atoms. These $3$ carbon atoms and $8$ hydrogen atoms would correspond to:

$3 / 1 = 3$ $\rm CO_2$ molecules, and
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