Explain how scientists know that the universe is expanding and who was the first to say this

Which statement describes the relationship of voltage and current?

How many joules of heat must be transferred to a 480-g aluminum pizza pan to raise its temperature from 22C to 234C? The specific heat of aluminum in this temperature range is 0.96 J/g•C. Show your work Q = mc (Tf-Ti)

What information is necessary to determine the atomic mass of the element chlorine? (1) the atomic mass of each artificially produced isotope of chlorine, only (2) the relative abundance of each naturally occurring isotope of chlorine, only (3) the

You see a quarter at the bottom of a fountain. Using what you know about light waves and refraction, predict what will happen when you reach down to get it in the position you perceive it to be. How does this relate to how rainbows are produced?

What are the origins of the word fossil

Describe your observations of the original solutions. Describe your observations when the silver nitrate was added to the sodium chloride solution.

A gas occupies 18.5L at stp. what volume will it occupy at 735 torr and 57°c?

When two elements form two different compounds, the masses of element B that combine with 1 g of element A can be expressed as a ratio of small whole numbers.

Which best identifies why the rusting of an iron nail in the presence of water and oxygen is in oxidation-reduction reaction

In the laboratory hydrogen gas is usually made by the following reaction:Zn (s) + 2HCl (aq) = H2 (g) + ZnCl2 (aq) How many liters of H2 gas, collected over water at an atmospheric pressure of 752 mmHg and a temperture of 21 Co, can made from 3.