Which of the following statements describes elements? a. Elements can be separated into simpler substances
b. The particles that make up an element are different from each other
c. Elements cannot be combined in a chemical reaction
d. Elements have unique sets of properties

Which statement describes james chadwick’s discovery.

Although respiratory organs vary across different organisms, they all contain respiratory surfaces that have a large surface area and are extremely thin. explain why having an extremely thin respiratory surface with a large surface area is advantageous for the process of gas exchange

What is the pressure of 0.500 moles of carbon dioxide gas in a 2.5 l tank and at a temperature of 301 k? (r=0.0821 l·atm/mol·k) 3.08 atm 1.2 atm 0.23 atm 4.01 atm 4.94 atm