Which of the following gases have the greatest root mean square velocity/speed?

The following image shows interactions between molecules of ethylamines (CH3CH2NH2). From the image identify the hydrogen bonds. 

Which of these ions has the largest radius (O2-, F-, Na+, or Mg2+)?

Using the data below on successive ionization energies, determine what the element could be?    Number of Electrons Removed  Ionization Energies (kJ/mol)   1  600  2  1200  3  3000  4  12,000  5  13,000  6  14,500  7  15,600 

Determine the amount of heat released (in kilojoules) when 12.20 grams of ethane, C2H6, undergoes combustion according to the following equation: 2C2H6 (g) + 7O2 (g)

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

Which of the following statement(s) is/are correct  Sample A can be a representation of a flask containing carbon monoxide gas.  Sample B can be a representation of a flask containing nitrogen dioxide gas. Sample C can be a representation of a flask containing helium gas and hydrogen gas. 

Which is the correct Lewis structure for COF2?

How many moles K3PO4 would be produced if 24 moles of KOH were used in the reaction? The balanced chemical equation is given below.                        3KOH  +  H3PO4 ⟶  K3PO4  +  3H2O

Use the theoretical chemical symbol below to determine is corresponding statements are true or false.    Element Z has 710 protons.  [1] Element Z has 405 neutrons.  [2] Element Z has 307 electrons.  [3]