Short Answer and Fill in the Blank

Practice Problems

Question #1

Short answer and fill in the blank

1. The horizontal rows of the periodic table are called………

2. The ions BrO4-, BrO2-, BrO- and BrO3- are named respectively as ………….., ……………., ……………………., …………………

3. Argon belong to the …………..group of the periodic table

4.  If the melting point of tungsten metal is 3422oC, what is its melting point in Kelvin? …………..

5.  What are the atomic number (Z), mass number (A) and symbol of the chlorine isotope with 18 neutrons?

6. When dissolved in water, LiOH behaves as …………………(acid or base)

Question # 2

A. Provide an acceptable name or formula.

Name

HIO4 ………………………….

K3PO4 ………………………….

P3O5 ………………………….

(NH4)2S ………………………….

Dichlorine heptaoxide …………………………..

Zinc (II) chromate …………………………..

Magnesium Nitride …………………………..

Phosphorous pentafluoride ………………………….

Question # 3

----- Cl2O7 + …….H2O à ………HClO4

…….Ca3(PO4)2 + ……H2SO4 à ……H3PO4 + …….CaSO4

2.  Write a balanced chemical equation for each of the following:

a.  Gaseous ammonia (NH3) reacts with gaseous oxygen to form gaseous nitrogen monoxide and gaseous water

b.  Liquid pentane (C5H12) reacts with gaseous oxygen to form carbon dioxide and liquid water

Question # 4

1.  The density of titanium is 4.51 g/cm3. What is the volume (in cm3) of 3.5 lb of titanium?

2.  The value of the Euro is currently 1.25 U.S and the price of 1 liter of gasoline in France is 0.97 Euro. What is the price of 1 gallon of gasoline in U.S dollar in France?

Question 5

A.  A combustion analysis of 2.19g of unknown compound containing carbon, hydrogen and oxygen produced 2.46 g of H2O and 4.63 g of CO2.

i.  What is its empirical formula?

C5H14O2

ii. What is its molecular formula if the molecular mass is 110.0 g/mol.

iii. What are the percent compositions of each atom by mass?

Question # 5

A.  Methyl salicylate (oil of wintergreen) is prepared by heating salicylic acid, C7H6O3 , with methanol, CH3OH

Molar mass of C7H6 O3 = 138.13 g/mol

Molar mass of CH3OH = 32.03 g/mol

Molar mass of C8H8O3 = 152.06 g/mol

C7H6O3 + CH3OH à C8H8O3 + H2O

Salicylic acid methanol methyl salicylate

In an experiment, 1.50g of salicylic acid is reacted with 11.20g of methanol. The actual yield of methyl salicylate, C8H8O3 is 1.31 g.

i.  What reactant is limited?

C7H6O3 is limited

ii. What is the percent yield of C8H8O3?

80.0%

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