A chemical or physical change that releases heat into its surroundings is ...

A. An exothermic process

B. melting ice

C. endothermic process

D. A phase change

Why is atmospheric pressure generally lower beneath a mass of warm air than beneath a mass of cold air?

The o-to-o-to-o bond angle in an ozone (o3) molecule is not exactly 120° because

Which list includes elements with the most similar chemical properties? 1. Br, Ga, Hg 2. Cr, Pb, Xe 3. O, S, Se 4. N, O, F

How are P waves different from S waves?

Which of the following would you predict to have a positive value for º? AgCl (s) → Ag + (aq) + Cl - (aq) H2O (g) → H2O (l) 2 Na (s) + Cl2 (g) → 2NaCl (s) Br2 (l) → Br2 (s)

How many particles are in 1 mole of a substance?

Initially you dissolved all, or most, of the p-aminobenzoic acid in ethanol. then you slowly added sulfuric acid. as you did this, a large amount of white solid formed. during the course of the reaction, that white solid dissolved.

How do you know if a chemical reaction has occurred?

Why must a container or system be closed for equilibrium to be established?

What is the bond angle between the hydrogen atoms in an ammonia (NH₃) molecule?