Chemistry:Understanding Matter

Question 1

Define Chemistry.

Answer 1

The study of matter and the changes it undergoes.

Question 2

Define Matter.

Answer 2

Anything that has mass and takes up space.

Question 3

Define Physical Properties.

Answer 3

Cause a physical change(colour, density, melting point, boiling point, state of matter.)

Question 4

Define Chemical Properties.

Answer 4

Describe how one substance reacts with another. A chemical property can only be identified once a substance ahs undergone a chemical reaction.

Question 5

Define Chemical Reaction.

Answer 5

Where matter changes to produce a new substance(s) with properties different from those original materials.

Question 6

Define Elements.

Answer 6

1 type of atom, cannot be broken down into simpler substances.

Question 7

Define Compounds.

Answer 7

Made of 2 or more elements chemically united, can be separated chemically into simpler elements.

Question 8

Define Mechanical Mixture(Heterogeneous).

Answer 8

Different components of the mixture are visible; composition is variable throughout the mixture.

Question 9

Define Solution(Homogeneous).

Answer 9

Different components are not visible; composition is constant throughout the mixture.

Question 10

Techniques to Separate Matter: Define Mechanical.

Answer 10

one or more components are picked out of the mixture either manually or by use of a magnet for magnetic substance.

Question 11

Techniques to Separate Matter: Define Settling.

Answer 11

some heterogeneous mixtures can be separated by letting one of the components settle tot he bottom. Spinning the mixture at a high speed(centrifuging) may be used to accelerate this process.

Question 12

Techniques to Separate Matter: Define Flotation.

Answer 12

Oil, detergents, or other chemicals are added to heterogeneous mixture and air is blown through. The froth containing the desired component floats and is skimmed off the surface. This technique is used to concentrate ores of zinc, copper, nickel, lead and to separate bitumen(tar) from sand.

Question 13

Techniques to Separate Matter: Define Filtration.

Answer 13

A heterogeneous mixture, usually a solid in a liquid or gas, is passed through a screen or filter. The solid is trapped and separated from the liquid or gas.

Question 14

Techniques to Separate Matter: Define Extraction.

Answer 14

The mixture is mixed with a solvent that dissolves one or more, but not all components. For example a coffee maker uses hot water to extract some of the components from ground coffee beans.

Question 15

Techniques to Separate Matter: Define Crystallization.

Answer 15

A dissolved solid is separated from a solution by cooling or concentrating the solution to crystallize the solid.

Question 16

Techniques to Separate Matter: Define Distillation.

Answer 16

A liquid mixture is boiled and one or more components are separated as they vaporize from the mixture.

Question 17

Techniques to Separate Matter: Define Chromatography.

Answer 17

A mixture is carried by solvent through a stationary, porous medium such as a column of solids or a filter paper. Separation occurs because components of the mixture move at different rates in the porous medium.