If a person can do 39J of work in 13 seconds, what is the amount of power?

How many days are required for 200. grams of radon-222 to decay to 50.0 grams? (1) 1.91 days (3) 7.64 days (2) 3.82 days (4) 11.5 days

What does the atomic number tell you about the atom of the element

You react an excess of hydrogen gas with 8.00 g of oxygen gas to form water (as shown in the balanced equation below). what mass of water is formed, assuming a complete reaction?

Read the following chemical equation. Al + Cl2 → AlCl3 Which of the following fractions can be used for the mole ratio to determine the mass of Al from a known mass of AlCl3? 2/1 3/2 2/2 2/3

Planck's equation E = h * v is used to determine which of the following? Question options: the energy released as an electron moves to a higher orbital the number of lines on the atomic spectrum for an atom the energy released as an electron moves

Adding drops of food coloring to a beaker of water more organized system?

Some chemical hazards are physical and some are related to the potential health effects of exposure. Click only one box for each response Toxicity Carcinogenic Flames Inhalation hazard Flying objects

Which would be best categorized as heat transfer by convection? A) Wearing a white shirt to stay cool on a summer day.

All the atoms of a particular element have the same number of neutrons. a. True b. False

For keeping goods cold during shipment, what is an advantage of dry ice (frozen carbon dioxide) pver water ice?