How many neutrons does an element have if its atomic number is 40 and its mass number is 154

What makes a material electrically conductive on the atomic level?

How does deforestation (cutting trees down), affect carbon dioxide levels in the atmosphere? A. Trees have no effect on carbon dioxide in the air. B.

1 - Oil Spill Pollution Problem Statement (it is written in the form of a question) 2 - Form a Hypothesis (an educated guess of what you think will happen)

Explain why samples of platinum and copper can have the same extensive properties but not the same intensive properties

Definition of isotopes

Given the following list from the activity series of metals (from most active to least active) K, Na, Al, Mn, Cr, Cd, Co, Pb, Hg which reaction would you NOT expect to occur? 1. Co²⁺ (aq) + Al (s) → Al³⁺ (aq) + Co (s) 2.

Chemical reactions that release energy A. will not occur. B. need catalysts to occur. C. will always explode. D. often occur spontaneously.

Which metal exist in liquid state and can be cut with knife?

Based on the ionization energies of the alkali metals, which alkali metal would you expect to undergo the least exothermic reaction with chlorine gas? Express your answer as a chemical symbol.

An atom of a particular element is traveling at 1.00% of the speed of light. The de Broglie wavelength is found to be 3.31 * 10-3 pm. Which element is this? Prove it.