According to the law of conservation of mass, mass is neither created nor destroyed in any ordinary chemical reaction. Which of the following is a demonstration of this law?

A compound is 52.14% C, 13.13% H, and 34.73% O by mass. What is the empirical formula of the compound?

What are members one through six of the alkyne family

Which of these answers best describe a fossil?

The number of grams of H2 in 1470 mL of H2 gas.

Which of the following is an example of a physical change? A) grinding coffee beans B) baking a cake C) converting water to hydrogen and oxygen D) digesting a cheeseburger E) burning coal

Which statement about scientific explanations is true? A. Scientific explanations are open to change. B. Scientific explanations are never reliable. C. Scientific explanations are always correct. D. Scientific explanations are rarely proven wrong.

Which of the following might a chemist choose to study? A. Glacier movement in Alaska B. Better ways to recycle plastics C. The effects of hurricanes on turtle populations D. The vibrations in bridges caused by big trucks

How many electrons would the element calcium need to be electrically neutral?

How to convert metric units?

President Nixon promised over $3 billion in economic aid to North Vietnam after the war. a. true b. false