Riley is doing an experiment working with friction. He wants to find two ways to modify an object that could increase or decrease the same type of friction.

Which methods could he use to perform his experiment?

molybdenum bromide is dissolved in water and lead nitrate added only one third of halogens is precipitated

Which ranks these materials by the attraction between their atoms from the weakest to the strongest? a. oxygen gas, liquid water, liquid honey, solid iron ore b. liquid water, liquid honey, oxygen gas, solid iron ore c.

Density is calculated by solving for mass divided by .

The mass of an atom of beryllium is 1.5 x 10^-26 kg. How many beryllium atoms are present in beryllium film of mass 0.37 g used as a window on an x-ray tube? Answer in units of atoms.

If 0.520 mol nitrogen has a volume of 17.0 L at some temperature and pressure, what volume would 0.750 mol carbon dioxide have at the same temperature and pressure?

Which topic is commonly used to explain activation energy and how chemical reactions happen A. reaction rate B. Collision theory C. Velocity distribution D. Spontaneous reaction

Calculate the density of a rectangular solid that has a mass of 25.71 g, and its dimensions are 2.3 x 4.01 x 1.82 cm.

When the metal sample reacts with acid, the gas evolved will be collected over water; the gas is said to be "wet".

Solid iron (II) sulfide reacts with aqueous hydrochloric acid HCl to produce hydrogen sulfide gas H2S and aqueous iron (II) chloride.

How are mixtures compounds and elements alike?