Essay on Elements, Compounds, and Mixtures

question

A chemist is studying an unknown substance. He can break it into its elemental components only by using chemical means. Q. Based on this observation, how should the unknown substance be classified?
answer

pure substance
question

A teacher makes the following statement. \”Gasoline boils at a relatively low temperature (about 150°C). The kerosene is removed at around 200°C, followed by diesel oil at 300°C and fuel oil at around 370°C.\” Q. What topic is the teacher most likely talking about?
answer

filtration of a pure substance
question

Which cannot be separated into simpler substances?
answer

element
question

The table describes how some substances were formed. Q.Based on the given descriptions, which substance is most likely a mixture?
answer

R
question

Which method would be best for separating the components of a mixture that is made from two different liquids?
answer

distillation
question

The chemical formula for emerald is Be3Al2(SiO3)6. An emerald can be described as
answer

a pure substance because it is a compound.
question

A solid precipitate is formed from the reaction of lead nitrate and sodium chromate. Q. What would be the best method to separate this solid from the solution?
answer

filtration
question

The table shows the percentages of hydrocarbons that are found in a sample of crude oil. Q.Based on the given information, what is the best classification for this sample of crude oil?
answer

a mixture
question

What can a drop of liquid mercury be described as?
answer

a pure substance and an element
question

A rock can be broken down into different kinds of substances by physical processes. No chemical reactions are needed to separate different parts of a rock into pure substances. This is because a rock is a(n)
answer

mixture

Get instant access to
all materials

Become a Member