Question

The average density of human blood is 1.06g/mL. What is the mass of blood (in kg) in an adult with a blood volume of 5.5 L?

Answer 1

First, let's convert 5.5 L to milliliters to cancel correctly when we use the formula. Remember that 1 liter equals 1000 mL:

`\text{5}.5\text{ L}\cdot\frac{1000\text{ mL}}{1\text{ L}}=5500\text{ mL.}`

Now that we have this value, we can find the mass using the formula:

`\begin{gathered} \text{density}=(mass)/(volume), \\ \text{mass}=\text{density}\cdot\text{volume.} \end{gathered}`

And replace the data that we have:

`\begin{gathered} \text{mass}=1.06(g)/(mL)\cdot5500mL, \\ \text{mass}=5830\text{ g.} \end{gathered}`

But we need to give the answer in kg, so remember that 1 kg equals 1000 g. The conversion from 5830 g to kg would be:

`5830\text{ g}\cdot\frac{1kg}{1000\text{ g}}=5.83kg.`

The answer is that the mass of blood is 5.83 kg in 5.5 L.