Which two elements most likely have the most similar properties?

beryllium and boron

scandium and silicon

nitrogen and phosphorus

hydrogen and helium

Which ocean floor sediment has its source on land manganese nodules sand salts calcium carbonate

Which state of matter is described as an electrically charged gas? Liquid Plasma Solid Vapor

Which weather condition commonly occurs along cold front?

Combustion vapor-air mixtures are flammable over a limited range of concentrations. The minimum volume % of vapor that gives a combustible mixture is called the lower flammability limit (LFL).

Which element has the greatest electronegativity? a. Chlorine b. Oxygen c. Sulfur d. Phosphorus e. Fluorine

Which situation describes evidence of a chemical change? A. When food color is added to water, it changes color. B. A solid changes into liquid when heated. C. A solution feels warm after a cool solid is added to it. D.

Identify the intermediate in the halogenation of alkanes. a) Anionb) Cationc) Radicald) Dimer

An archer pulls her bowstring back 0.370 m by exerting a force that increases uniformly from zero to 264 N. (a) What is the equivalent spring constant of the bow?

If 5.0g of KCLO3 is decomposed, what volume of O2 is produced at STP?

For metallic structures, does the packing efficiency (see sample exercise 12.1 in textbook) increase or decrease as the number of nearest neighbors (the coordination number) decreases?