What is the mass of a 1.69-l sample of a liquid that has a density of 0.921g/ml?

The mass is 1610 g.

D=MV, where D is density, M is mass, V is volume

Known/Given
D=0.921 g/mL
V=1.75 L×1000mL1L=1750 mL

Unknown
M

Equation
D=MV

Solution
Rearrange the equation to isolate the mass and solve for mass.

M=D×V=0.921g/mL×1750mL=1611.75 g=1610 g with three significant figures.

The following diagram helps to understand how to manipulate the density equation so solve for any of the variables.

The following Density Triangle will help you determine how to solve for any missing variable. Put your finger over the missing variable to see what you need to do to solve for it. For example, if you need to find volume, put your finger over the V, and you get M÷D.

https://www.teacherspayteachers.com/Product/Science-Journal-Density-Triangle-Foldable-Completed-4360...

the number of valence electrons for each molecule or ion is shown beneath the structure. remember hydrogen will not have more than two electrons. this hydrogen is part of a covalent bond (sharing two electrons). a double bond here would cause hydrogen to share four electrons with phosphorus.