Chem Unit 4 Review

Moles/Conversion

100

What is the number used to convert between molecules and moles?

Avogadro's Number 6.02x10²³

200

What is the molar mass of the compound  Fe₂O₃?

159.69 grams 

300

What is the mass in grams of 6.55 mol of H2O?

117.9 grams

400

How many moles is in 30 liters of liquid Neon?

1.34 moles

500

How many moles of of Bromide are in one mole of Nickel(II) Bromide?

2 moles

Density/Notation

100

Are trailing zeros considered sig figs? (i.e. 2000)

No

200

What is the scientific notation for 104,000

1.04 x 10⁵

300

What is standard notation for 2.056 x 10^-6

0.000002056

400

What is the mass of an object if has a density of 2 g/ml and a volume of 60 ml?

120 grams 

500

What is the density of an object that has a mass of 700 grams and a volume of 100 ml?

7 g/ml

Composition/sig fig

100

How many sig figs does the number 40001 have?

5

200

How many significant figures does the number 0.000443 have?

3

300

What are the three steps for finding the empirical formula from mass percent?

Divide each percentage by the atomic relative mass of the element.

Divide all the calculated values with the smallest value w

Make all of the answers a whole number by rounding or by multiply lowest multiple

400

What is the empirical formula of a compound that is 15.8% carbon and 84.2% sulfur?

CS₂

500

How much of a pearl (CaCO₃) is made up of Carbon? 

~12%

Chem Reactions/Equations

100

What is the opposite of a synthesis reaction?

Decomposition Reaction

200

What are some characteristics of a chemical reaction?

Change in color or temperature or odor 

Formation of precipitate

Evolution of gas and/or Appearance of bubbles

Change in state

Formation of new substances

Change in energy

300

_ Cs + _ N₂ -->  _ Cs₃N

6, 1, 2

400

What is the formula for a compound if it dissociated into 60 Li+ ions (Lithium) and 20 PO43- (Phosphate) ions?

Li₃PO₄ 

500

Balance: _FeCl3 + _NaOH → _Fe(OH)3 + _NaCl

_, 3, _, 3

Salts and Solubility

100

What are the 7 diatomic elements?

H, N, O, F, Cl, Br, I

200

Is mass lost during a chemical reaction?

No

300

Is the compound CaBr₂ soluble or insoluble?

Soluable

400

What is an electrolyte? Give an example of a compound

Compound that dissociates into ions when dissolved in water. (i.e they are soluable)

500

Is the compound BaCrO4 soluble or insoluble?

Insoluble