are asked to directly mass 5 grams of solid into a beaker you could either tare

the balance without the beaker or tare the balance with the beaker present.

If you will take a mass of something in the beaker at a later date, then you

should tare the balance before putting the beaker on it. This would lead to

recordings in your notebook of something like the following:

Mass of Empty Beaker: 101.568 grams

Mass of Beaker with Solid: 106.237 grams

Mass of Solid:

Alternatively, if you will not take the mass of an object in the beaker later, then

you could tare the balance after adding the beaker. This would lead to recordings

in your notebook of something like the following:

Mass of Solid: 4.669 grams

It certainly feels easier to just have the one value written down but be careful

that you won’t need the mass of the beaker later. If you are unsure about

whether you will need the mass of the beaker later, then it is best to record its

mass and follow the first approach. Although you will need to write down two

more numbers and do a little subtraction, it could save you in the end.

Separating a Heterogeneous Mixture and

Determining Masses

You will be provided with a mixture that contains sand (SiO₂), table salt (NaCl),

and benzoic acid (C₆H₅COOH). Your goal is to separate the mixture into its

components and determine the percent composition of each component in the

mixture.

Here is some basic information about the properties of sand, table salt, and

benzoic acid. We will use these properties to separate the three different solids

from each other. The table below lists how many grams of each substance will

dissolve in 100 grams of water at various temperatures in degrees Celsius.

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