Is barium a stable element why or why not?

Which statement accurately describes irregular galaxies? Irregular galaxies are much larger than spiral and elliptical galaxies. Irregular galaxies contain little gas and dust. Irregular galaxies contain many newly-formed stars.

The nucleus of an atom contains at least one proton. True or false

The decomposition of hi has a rate constant of 1.80 * 10-3 m-1s-1. how much hi remains after 8.50 min if the initial concentration of hi is 4.78 m?

A chemist adds 0.55 L of a 4.69M silver nitrate (AgNO3) olution to a reaction flask. Calculate the mass in kilograms of silver nitrate the chemist has added to the flask. Be sure your answer has the correct number of significant digits.

Classify the following as atoms or molecules. Drag the appropriate items to their respective bins. a. Mg S b. H2 SO3 c. HBr

Identify the spectator ions in the following complete ionic equation. 2k (aq) s2 - (aq) pb2 (aq) 2no-3 (aq) →pbs (s) 2k (aq) 2no-3 (aq) express your answers as ions separated by a comma.

4. A bird left its post and flew in a triangular path. It flew 21 yards south, 72 yards east and 75 yards diagonally to end back at the post. Is it a right triangle?

Condension occurs in the inside of your windows in Winters, why?

How can you use Hess's law to determine a reaction's enthalpy?

7. How much energy in KJ is released when 15.0 g of steam at 100.0 degrees Celsius is condensed and then frozen to ice at 0.0 degrees Celsius?