Chem League (DK014 24/25)- Final

What is the molarity of a solution formed from 6.75g NaCl dissolved in water to make a solution with a total volume of 0.452L?

• 0.255 mol L−1

• 0.0255 mol L−1

• 25.5 mol L−1

• 52.2 mol L−1

A sample of 0.892g of potassium chloride, KCl is dissolved in 54.3g of water. What is the percentage by mass of the solution?

• 0.162%

• 1.62%

• 16.2%

• 162%

What is the oxidation number of manganese, Mn in MnO4−?

• +7

• +6

• +5

• +4

The _____________ yield is the amount of product determined experimentally from a reaction.

• actual

• stoichiometry

• percentage

• theoretical

The order of filling orbitals is

• 1s 2s 2p 3s 3p 3d 4s 4p

  
  

• 1s 2s 2p 3s 3p 3d 4p 4s

  
  

• 1s 2s 2p 3s 3p 4s 3d 4p

• 4p 4s 3d 3p 3s 2p 2s 1s

Which of the following electronic configurations obey Hund’s rule?

• 
• 
• 
• 

Orbital can be defined as

• Two-dimensional region inside the nucleus where there is a high probability of finding an electron.

  
  

• Two-dimensional region in space around the nucleus where there is a high probability of finding an electron.

• Three-dimensional region inside the nucleus where there is a high probability of finding an electron.

• Three-dimensional region in space around the nucleus where there is a high probability of finding an electron.

  
  

The position of an element in the Periodic Table is determined by its

• atomic size

• proton number

• electronegativity

• chemical properties

How many valence electrons are in an atom of each element in Group 15 in the periodic table?

• 1

• 5

• 3

• 15

Select the total number of electrons for the Lewis dot symbol of an atom with electronic configuration
1s² 2s² 2p⁶ 3s² 3p³