the second worksheet of SCIENCE! for today
performing an experiment
read the following statements and then answer the questions.
1. a scientist wants to find out why sea water freezes at a lower temperature than fresh water.
2. the scientist goes to the library and reads a number of articles about the physical properties of solutions.
3. the scientist also reads about the composition of sea water.
4. the scientist travels to a nearby beach and observes the conditions there. the scientist notes that taste of the sea water and other factors such as waves, wind, air pressure, temperature, and humidity.
5. after considering all this information, the scientist sits at a desk and writes, "if sea water has salt in it, it will freeze at a lower temperature than fresh water.
6. the scientist goes back to the laboratory and does the following:
a. fills each of two beakers with 1 liter of fresh water.
b dissolves 35 grams of table salt in one of the beakers.
c.places both beakers in a freezer at a temperature of -1 C.
d. leaves the breakers in the freezer for 24 hours.
7. after 24 hours, the scientist examines both breakers and find the fresh water to be frozen. the salt water is still liquid.
8. the scientist writes in a notebook, "it appears that salt water freezes at a lower temperature than fresh water does."
. the scientist continues, "i suggest that the reason salt water freezes at a lower temperature is that sea water contains dissolved salts, while fresh water does not."
questions
a. which statement(s) contain conclusions?
b. which statement(s) contains a hypothesis?
c. which statement(s) contain observations?
d. which statement(s) describe an experiment?
e. in which statement is the problem described?
f. which statement(s) contain data?
g. which is the manipulated variable in the experiment?
h. what is the responding variable in the experiment?
okay so this is the worksheet, and i think i have submit the other worksheet too early, butt i will also be answering these questions in an hour, so if you could also explain or tell me what i need to know for this, then thank you very much tutors !
4 answers
However, here is some help:
An independent variable is the potential stimulus or cause, usually directly manipulated by the experimenter, so it could also be called a manipulative variable.
A dependent variable is the response or measure of results.
please check the following (and add statements if needed):
a. which statement(s) contain conclusions?
i think the ninth statement.
b. which statement(s) contains a hypothesis?
i think the fifth statement.
c. which statement(s) contain observations?
i think the seventh, the fourth, and the eighth statements.
d. which statement(s) describe an experiment ?
i think the sixth statement.
e. in which statement is the problem described ?
i think the first statement.
f. which statement(s) contain data?
i think the second third
i think the second and third statements.
g. which is the manipulated variable in the experiment?
i think the manipulated variable is the beaker that has salt in it.
h. what is the responding variable in the experiment?
i think the responding variable is which beaker or water that freezes the first.
tank you very much tutors.