Ch. 5, 6, & 11 conversion factor, density, light, & moles                  test     [70 points]       honors Chem

For problems involving calculations, show your work in an organized manner, include any relevant equation (or formula and conversion factor(s)), put the proper units in your calculations / answer, and have the proper number of significant figures in your answer.              

1.  Solve:   [10 points]

a.  2.0  +  3.00  =  ________

b.  2.0  ÷  3.00  =  ___________

c.  (2.5 * 10-3)  -  (3.5 * 10-4)  =  __________

2.  A 45.0 g cylinder has a diameter of 5.0 mm and density of 5.0 g / mL.  What is the height, in meters, of the cylinder ?  [10 points]

3.  What is the difference between the emission versus absorption of light, in terms of an electron’s energy level ?  [5 points]

4.   Write the following types of light:  red, x-rays, radiowave, green, ultraviolet     in terms of ascending order of  __.  [10 points]

a.  energy

b.  wavelength

5.  What is the average atomic mass of carbon in a sample containing  85 % ¹² C, 10 % ¹³ C, and 5 % ¹⁴ C ?  [5 points]

6.  solve:  [15 points]

a.  325 mg water  =  __  water molecules

b.  125 g calcium chloride =  __ moles of calcium chloride

c.   875 milllimoles of carbon dioxide =  __  grams of carbon dioxide

7.  What is the empirical formula of the compound (containing carbon, hydrogen, and oxygen) based on the following information, where the combustion of 1.5 g of the compound in excess oxygen produced 1.0946 g of water and 2.676 g of carbon dioxide.   [15 points]

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Ch. 5, 6, & 11 conversion factor, density, light, & moles                  retest  [70 points]       honors Chem

For problems involving calculations, show your work in an organized manner, include any relevant equation or conversion factor(s), put the proper units in your calculations / answer, and have the proper number of significant figures in your answer.       

1.  What is the energy of a photon of light with a wavelength of 875 cm ?  [10 points]

2.   The below figure represent the electron energy level in an atom (not drawn to scale).  Label the arrows (a, b, c, or d) as orange, green, gamma ray, or microwave.   [10 points] 

figure = arrows pointing  up / down among different electron energy levels

3.  write your answer using scientific notation; if it’s already in scientific notation, then write “in scientific notation”  [10 points]

a.  213.67  =  ____________________

b.  0.000237  =  __________________

c.  150.0  ÷  7.00  =  ________________

d.  7398 *  104  =  _________________

e.  7398 * 10-3  =  __________________

4.  solve  [15 points]

a.  725.0 inch³   =  __ L

b.  1,234,567 μm  =  __ km

c.  89 nm  =  __ cm

5.  What is the empirical formula of the compound (containing carbon, hydrogen, and oxygen) based on the following information, where the combustion of 1.5 g of the compound in excess oxygen produced 1.0946 g of water and 2.676 g of carbon dioxide.   [15 points]

6.  A 7.0 g object with a density of 2.2 g / cm³ was added to a graduated cylinder containing 12.3 mL of water; what is the volume in the cylinder after the addition of the object ?  [10 points]