Which of the following is a radioisotope used to date rock formations older than 50,000 years?

a. Carbon-14.

b. Uranium-235.

c. Cobalt-69.

d. Carbon-12.

Why did bohrs observations of gaseous elements not reveal a complete spectrum when the light was shone through a prism? explain

How many grams of sodium bromide must be dissolved in 400.0 g of water to produce a 0.500 molar solution? A20.0 g B52.18 C2.00 g D20.6 g

Calculate the solubility of silver oxalate, ag2c2o4, in pure water. ksp = 1.0 * 10-11 a. 1.4 * 10-4 m b. 8.2 * 10-5 m c. 5.4 * 10-5 m d. 3.2 * 10-6 m e. 2.5 * 10-12 m

Which time is most precise? Timers at a swim meet used four different clocks to time an event

In a closed container at 1.0 atmosphere, the temperature of a sample of gas is raised from 300K to 400K. What will be the final pressure of the gas? * A. 0.010 atm B. 0 atm C. 100 atm D. 1.3 atm

Which planets' orbits is the belt located between the main asteroid belt?

For the baeyer-villiger oxidation of cyclohexyl methyl ketone

What will happen if the density of an object is less than the density of water?

Which cannot be separated into simpler substances? compound element solution mixture

What jobs involve chesmistry