Theoretical basics of Inorganic chemistry

1.    A 0.455 g sample of magnesium is allowed to burn in 2.315 g of oxygen gas. The sole product is magnesium oxide. After the reaction, no magnesium remains and the mass of unreacted oxygen is 2.015 g. What mass of magnesium oxide is produced?

 

2.    A  0.382 g sample of magnesium is allowed to react with 2.652 g of nitrogen gas. The sole product is magnesium nitride. After the reaction, the mass of unreacted nitrogen is 2.505 g. What mass of magnesium nitride is produced?

 

3.    A 7.12 g sample of magnesium is heated with 1.80 g of bromine. All the bromine is used up, and 2.07 g of magnesium bromide is the only product. What mass of magnesium remains unreacted.

 

4.    We found that when 0.455 g of magnesium reacted with 2.315 g of oxygen, 0.755 g of magnesium oxide was obtained. Determine the mass of magnesium contained in a 0.500 g sample of magnesium oxide.

 

5.    What masses of magnesium and oxygen must be combined to make exactly 2.000 g of magnesium oxide?

 

6.    What substances are present, and what are their masses, after the reaction of 10.00 g of magnesium and 10.00 g of oxygen?

 

7.    Write the symbol for the atom that has an atomic number of 9 and a mass number of 19. How many electrons and how many neutrons does this atom have?

 

8.    What is the wavelength of the yellow sodium emission, which has a frequency of 5.09  ∙ 10¹⁴/s?

 

9.    Calculate the theoretical volume of air which will be required for completely burning 500 cubic feet (cft) of Acetylene gas (C₂H₂) if the air contains 21% of oxygen? All volumes are measured under the same conditions of temperature and pressure.

 

10.    In a combustion chamber 5L of carbon monoxide and 2.5 L of oxygen is led, both at 298 K and 1 atmosphere pressure. Assuming complete combustion and no loss of gas, what will be the volume of carbon dioxide formed at 298 K and 1 atmosphere pressure?

 

11.    A gas was found to have a density of 0.0847 g/L at 17.0 °C and a pressure of 760 torr. What is its molar mass? What is the gas?

 

12.    The red spectral line of lithium occurs at 671 nm (6.71 ∙ 10^-7m). Calculate the energy of one photon of this light.