A buffer solution is made using a weak acid, ha. if the ph of the buffer is 4 and the ratio of a - to ha is 0.001, what is the pka of ha?

Calculate the number of moles in each sample. part a 76.1 g h2ccl2

What elements mass number is 15

What is the name of the group of elements that have properties of both metals and nonmetals? Alkaline earth metals Alkali metals Metalloids Noble gases

Extrapolation allows you to estimate values greater than those in your actual data. True False

Give an example of at least one element made up of molecules and one compound made up of molecules.

How should scientist respond when new evidence that challenges current is presented?

Consider the following reaction, equilibrium concentrations, and equilibrium constant at a particular temperature. Determine the equilibrium pressure of H2. D2 (g) + H2 (g) ⇌ 2 HD (g) Kp = 1.80 P (D2) eq = 1.1 * 10-3 atm P (HD) eq = 2.7 * 10-3 atm

Find δe for the change in state of 1.0 molh2o (l) at 79 ∘c to h2o (g) at 116 ∘c. the heat capacity of h2o (l) = 75.3 j/molk, heat capacity of h2o (g) = 25.0 j/molk, and the heat of vaporization of h2o is 40.7*103j/mol at 100 ∘c.

Balloon A started with a volume of 1.76 L. The temperature of the room the balloon was in was 295 K. The balloon was heated to a temperature of 253.15 K. What is the new volume?

The standard internal energy change for a reaction can be symbolized as ΔU°rxn or ΔE°rxn. For the following reaction equations, calculate the energy change of the reaction at 25 °C and 1.00 bar. Sn (s) + Cl2 (g) - - - > SnCl4 (l) + H (KJmol) - 511.3.