The element oxygen, represented by the symbol O, is classified as

A. a compound.

B. a mixture.

c. a pure substance.

D.

a solution.

How many grams are there in one megagram

Select all the correct answers. Which of these statements are true about scientific theories and laws? Theories are untested. Laws are untested. Laws are often expressed as math formulas. A law is the same as a theory. Theories are not opinions.

Atoms in molecules share pairs of electrons when they make what type of bonds?

A controlled experment is designed to test a?

What part of the water cycle involves the leaves of plants

Which situation describes evidence of a chemical change? A. When food color is added to water, it changes color. B. A solid changes into liquid when heated. C. A solution feels warm after a cool solid is added to it. D.

Identify the intermediate in the halogenation of alkanes. a) Anionb) Cationc) Radicald) Dimer

An archer pulls her bowstring back 0.370 m by exerting a force that increases uniformly from zero to 264 N. (a) What is the equivalent spring constant of the bow?

If 5.0g of KCLO3 is decomposed, what volume of O2 is produced at STP?

For metallic structures, does the packing efficiency (see sample exercise 12.1 in textbook) increase or decrease as the number of nearest neighbors (the coordination number) decreases?