Question

Please Help! Explain if possible.

If an object has a density of 4.2 g/mL, what is its density in hg/L?

0.0042 hg/L
0.042 hg/L
42 hg/L
4,200 hg/L

Answer 1

42 hg/L

Solution:

Converting Grams into Hectograms:

As we know one gram is equal to 0.01 Hectogram. Using this relation we can convert 4.2 g into hg as,

1 g = 0.01 hg

So,

4.2 g = X hg

Solving for X,

X = (4.2 g × 0.01 hg) ÷ 1 g

X = 0.042 hg

We also know one millilitre (mL) is equal to 0.001 litre (L).

Therefore,

Density = Mass ÷ Volume

Putting new values,

Density = 0.042 hg ÷ 0.001 L

Density = 42 hg/L

Answer 2

42 hg/L

Solution:

Converting Grams into Hectograms:

As we know one gram is equal to 0.01 Hectogram. Using this relation we can convert 4.2 g into hg as,

1 g = 0.01 hg

So,

4.2 g = X hg

Solving for X,

X = (4.2 g × 0.01 hg) ÷ 1 g

X = 0.042 hg

We also know one millilitre (mL) is equal to 0.001 litre (L).

Therefore,

Density = Mass ÷ Volume

Putting new values,

Density = 0.042 hg ÷ 0.001 L

Density = 42 hg/L