Chemistry Sem 1 Unit 1 The Study of Chemistry Mid-Unit

Joseph Priestley discovered and described the chemical properties of oxygen.

What type of chemist would he be considered today?

• biochemist

• inorganic chemist

• physical chemist

• organic chemist

When placed in a 100 mL square box, a substance takes the shape of the box and has a volume of 100 mL.

When placed in a 50 mL circular tube, that same substance takes the shape of the tube and has a 50 mL volume.

In which state is the substance?

• solid

• liquid

• gas

Which term describes a piece of pure gold?

• compound

• element

• solution

• mixture

Which separation method is used in making coffee at home?

• chromatography

• simple distillation

• fractional distillation

• filtration

A chemist is testing the quality of a wine produced by a vineyard.

Which branch of chemistry might the chemist use?

• analytical chemistry

• inorganic chemistry

• physical chemistry

• organic chemistry

A substance undergoes a change.

Which statement indicates that the change was a physical change?

• Heat energy was given off.

• The substance changed shape.

• The molecules of the substance changed.

• The substance changed color.

The air temperature surrounding an icy windshield is 0°C. The driver turns on the defroster and the ice melts.

Which statement is true?

• The ice absorbed chemical energy to produce a chemical change.

• The ice absorbed heat energy to produce a chemical change.

• The ice released heat energy to produce a physical change.

• The ice absorbed heat energy to produce a physical change.

You have three molecules of sodium bicarbonate 3NaHCO₃

.

Which statement is true?

• The number of carbon atoms (C)

  is three times greater than the number of hydrogen atoms (O)

  .

• The number of oxygen atoms (O)

  is less than the sum of the sodium (Na)

  , hydrogen (H)

  , and carbon (C)

  atoms.

• The number of oxygen atoms (O)

  is greater than the sum of the sodium (Na)

  , hydrogen (H)

  , and carbon (C)

  atoms.

• The number of sodium atoms (Na)

  equals the number of carbon atoms (C)

  .

Steve, Sarah, Richard, and Kate each run paper chromatography on unknown liquids. Steve gets a red band, Sarah gets a yellow band and a red band, Richard gets a green band and a red band, and Kate gets a yellow band and a blue band.

Which student might have had a pure substance?

• Steve

• Sarah

• Richard

• Kate

Which term best describes a soft drink?

• heterogeneous mixture

• pure substance

• homogeneous mixture

• compound