What mass of NaCN must be added to create 250.0 mL of a buffer solution with a pH = 9.00 and an HCN concentration of 0.100 M? The pKa of hydrocyanic acid is 9.31.

Which statements accurately describe atoms? Check all that apply. Atoms cannot be divided. There are only a few different types of atoms. A single atom can be seen using a standard microscope. Atoms were named in the fifth century BCE.

Metallic magnesium reacts with steam to produce magnesium hydroxide and hydrogen gas. a. If 16.2 g Mg are heated with 12.0 g H2O, what is the limiting reactant? b. How many moles of the excess reactant are left? c.

Zinc reacts with hydrochloric acid according to the reaction equation how many milliliters of 3.50 m hcl (aq) are required to react with 2.25 g of zn (s) ?

How much energy is needed to melt 25.4 grams of l2

Consider the balanced equation for the following reaction: 3CuO (s) + 2NH3 (g) → 3H2O (l) + 3Cu (s) + N2 (g) If 17.3 grams of CuO reacts with 81.4 grams of NH3, how much excess reactant remains?

Using special equipment which layer of the sun atmosphere is visible during a total solar eclipse

The characteristic flame test colors of metal ions are due to atomic emission spectra. Duscuss the relationship between the absoption and emission of light and the factors responsible for flame test colors.

Should a bartender use ice and scoop directly from ice machine or use an ice holding device and scoop to make drinks and refill drinks from

What classification should this reaction have? 4Al + 3O2 → 2Al2O3

If you start with 100 grams of a radionuclide, how much will you have after two half-lives have passed?