Which two elements most likely have the most similar properties?

beryllium and boron

scandium and silicon

nitrogen and phosphorus

hydrogen and helium

An element can be identified by the number of In the nucleus of its atom.

The formula of the hydrogen ion is often written as

Which factor explains why coal dust in an enclosed space is more explosive than coal dust blown outdoors into an open space? A. Temperature. B. surface area C. concentration D. Volume E. catalyst

What is true of the relationship between electrons and protons? A. they have the same volume B. they have the same mass C. they have the same magnitude charge D. they have the same location

Which statement correctly describes diamond and graphite, which are different forms of solid carbon? (1) They differ in their molecular structure, only. (2) They differ in their properties, only.

Ions that consist of a single atom are called ... ions

Ecosystems are clearly separated from one another. Where one ecosystem stops, another begins A: True B: False

Mass_mole relationship

What is the momentum of an 800-kg car | traveling at a velocity of 10 m/s? What is its momentum if it speeds up to 50 m/s?

How many grams of CuSO4 are there in 100.0 g of hydrate? How many moles?