The half-life of cobalt-60 is 5.20 yr. how many milligrams of a 2.000-mg sample remain after 10.50 years?

Time (s) [NO2] (mol/L) 0 0.500 1,200 0.444 3,000 0.381 4,500 0.340 9,000 0.250 (Note: The rate law only depends on the concentration of NO2.) Consider the reaction NO2 (g) + CO (g) → NO (g) + CO2 (g).

Explain why samples of gold and copper can have the same extensive properties, but not the same intensive properties

Which scientific tools are used by life scientists

Which of these processes indicates that smelting copper is a chemical change? It involves melting copper to form liquid metal. It involves heating charcoal to high temperatures. It involves drawing copper into long wires.

Where do new root cells from? A. behind the root cap B. inside root hairs C. on top of the root cap D. under the cortex

Identical forces act for the same length of time on two different masses. The change in momentum of the smaller mass is A) smaller than the change in momentum of the larger mass, but not zero. B) zero.

How many nuclei of 238 92 U 92 238 U remain in a rock if the activity registers 290 decays per second? (Note that the half life of Uranium-238 is 4.468x109 years)

A base can neutralize an acid. true or false

Hydrochloric acid (12.0 ml of 0.233 m) is added to 296.0 ml of 0.0579 m ba (oh) 2 solution. what is the concentration of the excess h + or oh - ions left in this solution?

Which are the organs of the digestive system