how does mass change during a chemical reaction

What environmental conditions contributed to the heat wave experienced in Europe and caused thousands of deaths in France?

What else is necessary in order for a hydrogen atom in a molecule to participate in a hydrogen bond?

Whenever two measurements are equal or equivalent a ratio of these two measurements will equal what?

Which organelle contains chromosomes? A. nucleus B. mitochondrion C. chloroplast D. vacuole

A 5.018 gram sample of a certain hydrate of magnesium sulfate, MgSO4•xH2O, is heated until all the water is driven off. The resulting anhydrous compound weighs 2.449 grams. What is the formula of the hydrate?

What will happen if the density of an object is less than the density of water?

Which cannot be separated into simpler substances? compound element solution mixture

What jobs involve chesmistry

Think about a neutral magnesium atom. Then think of a magnesium ion with a 2+charge. How are these two alike? How are they different? Be sure to use the terms proton, neutron, and electron in your answer.

What subatomic particle is specifically responsible for combining the atoms together to form a new substance?