Question

review 2011 chemistry final semester 1
name
pg 3

1. define the following three terms:pg36

a. matter
b. compound
c. atom

1. what is the symbol for aluminium, gold, silver, and mercury, lead?pg124
2. list the symbols and names for 5 transitions metals with more than one charge: (name, symbol & charges) pg124
3. if a material contains three elements joined in a fixed proportion, it is a(n) ______________ pg36
4. define the term mixture?pg32

5a. give 4 examples of what a mixture might be?pg32
a.
b.
c.
d.

1. list characteristics of a mixture?pg32

6a. what are two types of mixtures: pg32
______________ is a well mixed mixture
______________ is not a well mixed mixture; can pick parts and pieces
pg32

1. a mixture that appears to contain only one substance is a(n) ______________
2. give 4 examples of the following type of mixture: heterogeneous mixture?pg32

a.
b.
c.
d.
9.define the term malleable: pg125
9a. give 4 examples of substances that are malleable? pg124
a.
b.
c.
d.

1. use the following physical properties to identify the following substance: the substance has a melting point of 0°c and a boiling point of 100°c. the substance is most likely: ______________ pg74
2. a material that is malleable and conducts electricity is most likely a ______________ pg124
3. filtration can be used to separate mixtures based on ______________ internet
4. when a physical change in a sample occurs, what does not change? ______________ pg31
5. give 4 examples of physical change?pg31

a.
b.
c.
d.

1. flammability and combustibility is a material’s ability to burn in the presence of ______________
2. a substance that has high reactivity will ______________
3. what is the most important safety rule while in the lab?
4. how is 0.00025 written in scientific notation? ______________
5. timers at a swim meet used four different clocks to time an event. which recorded time is the most prec

pg58 - 29
a. 44 s
c. 44.36 s why? ______________
b. 44.3 s
d. 44.365 s

1. on the celsius scale, at what temperature does water boil? ____________ freeze? ____________

Explanation:

Question 18:

Step 1: Recall scientific notation rules

Scientific notation is of the form \( a \times 10^n \), where \( 1 \leq |a| < 10 \) and \( n \) is an integer. For a number less than 1, we move the decimal point to the right until we get a number between 1 and 10, and the exponent \( n \) is negative (equal to the number of places we moved the decimal).

For \( 0.00025 \), we move the decimal point 4 places to the right to get \( 2.5 \). So the exponent \( n = -4 \).

Step 2: Write in scientific notation

So \( 0.00025 = 2.5 \times 10^{-4} \)

On the Celsius scale, water is a common substance with known boiling and freezing points. By definition, the boiling point of water (at standard atmospheric pressure) is 100°C, and the freezing point (or melting point) is 0°C.

Answer:

\( 2.5 \times 10^{-4} \)

Question 20: