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A 36.1 g sample of an unknown metal is heated from 15oC to 25oC and 130 J of heat is absorbed. Use the chart below to identify the unknown metal.  

The reaction of solid silicon (Si) with gaseous oxygen can be used to produce silicon trioxide. How many grams of silicon trioxide are produced in the reaction when 4.25 g of silicon reacts with 3.75 g of oxygen gas?    2Si (s) + 3O2 (g)

Which of the following is the correct formula for the chlorite ion? 

Use the theoretical chemical symbol below to determine is corresponding statements are true or false.    Element Z has 335 protons.  [1] Element Z has 415 neutrons.  [2] Element Z has 333 electrons.  [3]

How many sigma and pi bonds are in the structure below?

Which of the following electron transitions would emit energy?   a. n=5 → n=3  b. n= 2 → n=4 c. n=3 → n=6

Using the data below on successive ionization energies, determine what the element could be?    Number of Electrons Removed  Ionization Energies (kJ/mol)   1  1000  2  2000  3  5000  4  7,500  5  21,000  6  23,000  7  25,000 

Determine if the following molecules are polar. 1 is [1] 2 is  [2] 3 is [3]  4 is [4] 

Choose the correct name for FeS2?  

The scale of secondary sexual characteristics that is used by the health professionals to assess the degree of pubertal maturation among adolescents, irrespective of chronological age, is called the: