Question

Question #0c887

Answer 1

This solution is 10% concentration by mass.

Explanation:

A solution's percent concentration by mass is defined as the mass of solute, in your case the dissolved solid, divided by the total mass of the solution and multiplied by 100.

Since you're adding 4 g of solute in 36 g of solvent, which in your case is water, your solution will have a total mass of

`m_"sol" = m_"solid" + m_"Water"`

`m_"sol" = 4 + 36 = "40 g"`

Therefore, the percent concentration by mass will be

`"%w/w" = m_"solid"/m_"sol" * 100`

`"%w/w" = (4cancel("g"))/(40cancel("g")) * 100 = color(green)("10%")`