Identify the force used on your arm when you walk a dog on a leash and it tries to chase something. Friction
Gravity
Strong pull
Weak push

What are the 4 phases of matter in order of increasing engery content?

El amoniaco y el fluor reaccionan para formar tetrafluoruro de dinitrogeno y fluoruro de hidrogeno. segun la reaccion: nh3 + f2 ⇒ n2f4 + hf si reaccionan 5 gramos de amoniaco y 20 gramos de fuor, ¿cuantos gramos de fluoruro de hidrogeno se producen?

How many grams of oxygen gas will react completely with a block of calcium metal that is 3.0 cm by 3.5 cm by 4.2 cm, if the density of calcium is 1.55 g/ml? show all steps of your calculation as well as the final answer.