Iodine-131 is a radioactive isotope with a half-life of 8 days. how many grams of a 64 g sample of iodine-131 will remain at the end of 24 days?

Do molecules have protons?

Yo peeps! Important question: What does the colors blue, purple, green, and yellow mean on a mood ring?

At constant volume, you cool a sealed, air-filled can, and the pressure reduces by half. What happens in this situation? The number of collisions per unit area doubles. The spaces between the gas molecules shrink.

1. Addition of which of the following will increase the solubility of CaCO3 in water? Consider the equilibrium process: CaCO3 (s) Ca2 + (aq) + CO32 - (aq) Carefully consider common ions, and whether any species present in solution can react with the

Which of the following is a measure of the average kinetic energy of the particles in a sample of matter? A. chemical kinetics B. thermochemistry C. reaction rate D. temperature

Which physical method can be used for obtaining a sample of salt from a small beaker of salt water? boiling freezing chromatography sorting

Science is a unique field of thought because it relies on to describe the world. •Observations and experim •Teachers and students •Books and writings •Scientists and statements

Hemoglobin, a protein in red blood cells, carries o2 from the lungs to the body's cells. iron (as ferrous ion, fe2+) makes up 0.33 mass % of hemoglobin. if the molar mass of hemoglobin is 6.8 Ã 104 g/mol, how many fe2 + ions are in one molecule?

What could you predict about a methane molecule that would most likely be made by using both the quantum model of the atom and John Dalton's model?

What is the molar mass of an unknown hydrocarbon whose density is measured to be 1.97 g/l at stp?