If element X has 49 protons, how many electrons does it have? Your Answer:

1. A substance has a volume of 2.6 * 10-1 m3 and a mass of 210 g. Determine the density of the sample and express your results in kg/m3 with appropriate scientific notation. Make sure to show all work.

Which of the following solvents are polar? (eg Have an overall molecular dipole) (Hexanes, Ethyl Acetate, Ethanol) Ethyl acetate Ethyl acetate and ethanol Ethanol Hexanes Ethyl acetate and hexanes

According to le Châtelier's principle if a system in equilibrium is subjected to a change in all BUT one of these conditions, there will be a tendency for a net reaction in the direction that reduces the effect of this change.

True or False? Sodium is a very reactive metal.

Ionic compounds are formed by the ... of electrons? by the what?

Andy has two samples of liquids. Sample A has pH of 4, and sample B has a pH of 6. what can Andy conclude about these two samples? Sample A is a neutral b alkali c acidic Sample B is a neutral b alkali c acidic

How does a lone pair contribute to molecular shape? A. It is too small to affect the molecule's shape. B. It takes up space like an "invisible" atom. C. It forces the molecule into a tetrahedral shape. D. It lets the bonding pairs spread out more.

The are of a rectangle is 12 in^2. what is the area in cm^2. there are 2.54cm in an inch.

Which statements describe advantages of models? Check all that apply. Models make it possible to easily notice patterns. Models can be used to communicate and test design ideas. Models allow scientists to predict relationships.

Are energy levels and orbitals the same thing?