The Ka of H2CO3 is 4.3 × 10-7. What is the pH of a buffer with 0.10 M H2CO3 and 0.10 M NaHCO3?

The number of neutrons in an isotope of an atom is equal to

How many moles of iron are present in 3.15 x 1024 atoms of iron

Silicon has three naturally occurring isotopes: Si-28 (mass = 28.0 amu); Si-29 (mass = 29.0 amu), and Si-30 (mass = 30.0 amu). If the average atomic mass of silicon is 29.1 amu, which isotope is the most abundant?

Find the mass of AlCl3 that is produced when 25.0 grams of Al2O3 reacts with excess HCl according to the following reaction. Al2O3 (s) + 6 HCl (aq) –> 2 AlCl3 (aq) + 2 H2O (l)

The volume of a gas with a pressure of 1.2 atm increases from 1.0 L to 4.0 L. What is the final of the gas, assuming no change in the amount of gas or temperature?

How many grams of hydrogen are needed to produce 1.80 g of water according to this equation? 2 H2 (g) + O2 (g) –> 2 H2O (l)

Of the elements: B, C, F, Li, and Ne, the element with the largest atomic radius is

Given the following equation, what is the correct form of the conversion factor needed to convert moles of O2 reacted to the number of moles of Fe2O3 produced? 4 Fe(s) + 3 O2 (g) –> 2 Fe2O3 (s)

What is the coefficient of hydrogen H2 when the following equation is balanced? Al (s) + H2SO4 (aq) –> Al2(SO4)3 (aq) + H2