Below is a table which shows the melting(液化)and boiling points of common
substances.Study the table.Then do Numbers 4—7.
Substance
| Melting point(C)
| Boiling Point(C)
|
Water
Alcohol
Nitrogen
Oxygen
| 0
–117
–210
-218
| 100
78
–196
–183
|
小题1:The underlined word‘substances'means‘a type of'_________.
| A．matter | B．liquid |
| C．solid | D．gas |
小题2:Which of the four should be a liquid at-90 degrees?
| A．water | B．alcohol |
| C．nitrogen | D．oxygen |
小题3:Mixing alcohol and water is often used to wash windscreens of cars during the wintertime because _________.
| A．it is easier for alcohol to change into gas |
| B．alcohol is not easily separated from water |
| C．alcohol freezes at lower temperature than water |
| D．the mixture is not expensive |
小题4:In order to change water from a solid to a liquid energy must be _________.
| A．removed | B．added |
| C．created | D．destroyed |
