The number of blank in an atom of an element is the element's atomic number

Which of these gives an example of the influence of location on what kinds of organisms can survive in a biome? A) A pine tree grows well in a taiga evergreen forest in Canada, while a barrel cactus grows well in a desert in Arizona.

Mercury-210 has a half life of 10 minutes. What percent is left after 40 minutes?

A team of researchers is investigating a new carbon-rich molecule important to life. They find evidence for the presence of a carbon-carbon double bond in the molecule. This observation means that the new molecule likely exists as _.

B, C, O, F, and N are p-block elements. What is the correct order of reactivity of these elements (from greatest to least) ?

If you have 3x10^23 caffeine molecules, approximately how many miles of caffeine do you have?

Why do two isotopes of an element have the same atomic number but different mass numbers?

In a water solution, HCl and NaOH react to form H2O and NaCl. Radium-226 undergoes alpha decay to form radon-222. The temperature of both of these reactions is increased.

Which of these statements is true about endothermic reactions, but not about exothermic reactions? The reactants and products are different substances. The reactants have less energy than the products. The temperature of the container increases.

Calculate H3O + when OH - is 2*10 - 8

An element and an atom are different but related because a) A particular element is made up of many different types of atoms b) A molecule is the same as an atom c) An element is made up of all the same type of atom d) An element is smaller than an