Chem - Ch 1 + 3 Flashcards Preview

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Flashcards in Chem - Ch 1 + 3 Deck (31)
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1
Q

What is the scientific method

A

a logical, Systematic approach to the solution of a problem

2
Q

What is chemistry

A

the study of the composition of matter and the changes that matter undergoes

3
Q

What is an observation

A

when you use your senses to obtain information

an observation can lead to a question

4
Q

What is an interpretation

A

information acquired through observing something and then using prior knowledge to make a conclusion about it

5
Q

What is a hypothesis

A

a proposed explanation for an observation

6
Q

What is an experiment

A

a procedure that is used to test a hypothesis

7
Q

What is the independent variable

A

the variable that you change during an experiment

also called the manipulated variable

8
Q

What is the dependent variable

A

the variable that is observed during the experiment

also called the responding variable

9
Q

What is a model

A

a representation of an object or an event when doing a difficult/impossible experiment (like w atoms)

10
Q

What is a theory

A

a well-tested explanation for a broad set of observations

11
Q

What is a scientific law

A

a concise statement that summarizes the results of many observations and experiments

12
Q

Do the steps of the SM always have to be followed in order

A

no because you can do different parts of it multiple times before you even do one step (4 hypotheses/experiments before 1 theory)

13
Q

What is the difference between a theory and a law

A

a law states a fact, and a theory tries to explain why that fact occurs

14
Q

What is the difference between the world’s meaning of the word theory and the scientific meaning

A

The world takes it to really mean hypothesis, but scientifically it’s very reliable. There is a possibility that a theory may need to be changed at some point in the future to explain new observations/results

15
Q

What is the difference between a theory and a hypothesis

A

[insert definitions of both] + a theory is basically a repeatedly well tested hypothesis that covers a large range of observations

16
Q

What is the metric system based on

A

powers of 10

17
Q

What is 1 mL the same as

A

1 cm3

18
Q

What is temperature

A

a measure of how hot or cold an object is

19
Q

What is density

A

the ratio of the mass of an object to its volume

20
Q

How can 4 10g objects have different volumes?

A

if the 4 objects have different densities

21
Q

Does the density of a substance depend on the size of the sample

A

no, density only depends on the composition of a substance, no on the size of the sample

22
Q

What happens to the density of a substance as temperature increases

A

the density decreases

23
Q

What is the equation for density

A

d = m/v

24
Q

What is the equation for slope

A

rise over run

y1 - y2 over x1 -x2

24
Q

What do the slopes represent

A

The density of our objects

25
Q

Are the slopes different for our two sets of objects, why or why not?

A

Yes, because the masses and volumes (and therefore, densities) are different in each set, which would make the slopes different

26
Q

What are good experiment errors

A
  • estimating water levels wrong
  • object wet before u weigh it
  • wet fingers
  • not checking water level each time
  • splashing water
27
Q

How do you think that type of container used to measure volume affected your results

A

Some containers are more precise than others (graduated cylinder vs beaker, for example), so depending on the type of container you used, your results could be more or less accurate

28
Q

Which of your objects is most dense? How do you know?

A

Whichever one had bigger slope (since slope was the average densities of each object)

29
Q

As the density of a substance increases, the volume of a given mass of that substance…

A

Decreases

30
Q

If there is uncertainty in your measurements, how will your points fit the slope?

A

They won’t fit very well