Which of the following ions would represent the ion of an element from group 2A

Which of the following equations describes a single-replacement reaction? A. 2N2O5 (g) = O2 (g) + 4NO2 (g) B. 2Na (s) + Cl2 (g) = 2NaCl (s) C. Cl2 (g) + 2Kl (s) = 2KCl (s) + l2 (g) D. H2 (g) + Br2 (g) = 2HBr (g)

Charge is applied to a circular disk of ebonite of radius by rubbing it while it is rotating. In this way the surface charge density becomes proportional to the radial distance from the center.

What do you call the curved, upper surface of water that commonly appears when using a graduated cylinder?. Describe what causes this?.

What are three conditions that can cause chemical reactions to occur?

Which of the following has more energy? a. an ice cube. b. a glass of water in the fridge. c. A glass of water that has been sitting in the sun d. a glass of cold water from the faucet

Which would not be classified as a pure substance?

According to Boyle's law, how would you reduce the volume of a gas? a. by decreasing its pressure b. by increasing its temperature c. by decreasing its temperature d. by increasing its pressure

To what chemical reaction class does this reaction belong? 2 mg (s) + o2 (g) 2 mgo (s)

Which best illustrates how particle arrangement changes when solids change into liquids

Express in scientific notation (6.0x10^4) (3.1x10^-1)