pretest 1

Question 1

The statement, “In a chemical reaction, matter is neither created nor destroyed” is called…

Answer 1

The Law of Conservation of Mass.

Question 2

Molecules can be described as…

Answer 2

Two or more atoms chemically joined together.

Question 3

Which of the following statements about the phases of matter is TRUE?
A) In both solids and liquids, the atoms or molecules pack closely to one another.
B) Solids are highly compressible.
C) Gaseous substances have long-range repeating order.
D) There is only one type of geometric arrangement that the atoms or molecules in any solid can adopt.
E) Liquids have a large portion of empty volume between molecules.

Answer 3

A) In both solids and liquids, the atoms or molecules pack closely to one another.

Question 4

Systematic error is defined as…

Answer 4

Error that tends to be too high or too low.

Question 5

5) Which of the following are examples of a chemical change?
A) copper building materials develop a green patina over time
B) a candle burns
C) rubbing alcohol evaporates
D) Both A and B are examples of chemical change.
E) All of the above are examples of chemical change.

Answer 5

D) Both A and B are examples of chemical change.

Question 6

How many significant figures are in 0.00523980 mL?

Answer 6

6 Significant Figures.

Question 7

Which of the following numbers has the greatest number of significant figures?
A) 0.5070
B) 0.201
C) 418000
D) 6.02 × 1024

Answer 7

A) 0.5070 (4 Sig. figs.)

Question 8

Convert 35 m^3 to liters.

Answer 8

3.5 × 104 L

Question 9

What answer should be reported, with the correct number of significant figures, for the following
calculation? (433.621 - 333.9) × 11.900

Answer 9

1.19 × 10^3

Question 10

Which of the following is the smallest volume?
A) 22 cm3
B) 0.50 dL
C) 2.8 × 10^3 mL
D) 5.0 × 10^7 nL

Answer 10

A) 22 cm^3

Question 11

A mass of mercury occupies 0.950 L. What volume would an equal mass of ethanol occupy? The
density of mercury is 13.546 g/mL and the density of ethanol is 0.789 g/mL.

Answer 11

16.3 L

Question 12

Calcium belongs to the ________ group of the periodic table.

Answer 12

Alkaline earth metal

Question 13

In which of the following sets do all species have the same number of electrons?
A) F-, Ne, Mg2+
B) Ge, Se2-, BrC)
K+, Rb+, Cs+
D) Br, Br-, Br+

Answer 13

A) F-, Ne, Mg2+

Question 14

Identify an anion.

Answer 14

An atom that has gained an electron.

Question 15

Identify a cation.

Answer 15

An atom that has lost an electron.

Question 16

Which of the following elements is a halogen?
A) Kr
B) S
C) Br
D) Fe

Answer 16

C) Br

Question 17

Predict the charge that an aluminum ion would have.

Answer 17

3+

Question 18

Calculate the atomic mass of silver if silver has 2 naturally occurring isotopes with the following
masses and natural abundances:
Ag-107 106.90509 amu 51.84%
Ag-109 108.90476 amu 48.46%

Answer 18

108.19 amu

Question 19

How many moles of Kr are contained in 398 mg of Kr?

Answer 19

4.75 × 10^-3 moles Kr

Question 20

How many iron atoms are contained in 354 g of iron?

Answer 20

3.82 × 10^24 Fe atoms

Question 21

How many atoms of oxygen are in 2.50 moles of CO2?

Answer 21

3.01 x 10^24 atoms

Question 22

Which of the following are examples of physical change?
A) dew forms on a blade of grass
B) a halloween light stick glows after shaking
C) browning meat
D) hydrogen balloon explodes when contacted with a flame

Answer 22

A) dew forms on a blade of grass

Question 23

How many moles contain 2.16 x 10^24 atoms of silver?

Answer 23

3.59 moles

Question 24

Determine the molecular formula of a compound that has a molar mass of 183.2 g/mol and an
empirical formula of C2H5O2

Answer 24

C6H15O6

Question 25

``` Which of the following elements is a gas at room temperature? A) bromine B) carbon C) helium D) sodium ```

Answer 25

C) helium

Question 26

A covalent bond is best described as...

Answer 26

The sharing of electrons between atoms.

Question 27

Write the name for Sn(SO4)2. Remember that Sn forms several ions.

Answer 27

Tin (IV) sulfate

Question 28

``` Which of the following exists as a polyatomic molecule? A) neon B) carbon C) phosphorus D) lithium E) krypton ```

Answer 28

C) phosphorus

Question 29

``` Which of the following is an ionic compound? A) NaBr B) CO2 C) PCl3 D) CCl4 E) SeBr2 ```

Answer 29

A) NaBr

Question 30

Write the formula for copper (II) sulfate pentahydrate.

Answer 30

CuSO4 ∙ 5H2O

Question 31

Give the formula for sulfurous acid.

Answer 31

H2SO3

Question 32

Calculate the molar mass of Al(C2H3O2)3

Answer 32

204.13 g/mol

Question 33

Calculate the mass percent composition of lithium in Li3PO4.

Answer 33

17.98 %

Question 34

Determine the molecular formula for a compound that is 70.79% carbon, 8.91% hydrogen, 4.59% nitrogen, and 15.72% oxygen.

Answer 34

C18H27NO3

Question 35

Li2S is named...

Answer 35

lithiium sulfide.

Question 36

How many atoms of carbon are contained in 47.6 g of Al2(CO3)3? The molar mass of Al2(CO3)3 is 233.99 g/mol.

Answer 36

3.68 × 10^23 C atoms