Select the correct answer.

The chemical composition of most stars usually has which element in the highest concentration?

A. oxygen

B. hydrogen

OC. chromium

OD. lead

Organic chemistry involves which type of study? A. The study of compounds and chemicals containing carbon, which include pharmaceuticals, drugs, and plastics. B. The study of matter and processes that occur in biological organisms. C.

Given the balanced equation representing reaction: N2 + energy = = > N + N Which statement describes this reaction? (I) Bonds are broken, and the reaction is endothermic. (2) Bonds are broken, and the reaction is exothermic.

How is the soap making process an acid/base reaction? Use evident to support your claim.

How is heat produced in a chemical change

Use the periodic table to answer the questions which is the correct electron configuration for titanium

The Doppler effect indicates that the universe is expanded because A. light from other galaxies is different colors B. light from other galaxies are blue shift C. light from other galaxies are red shift D. light from other galaxies is the same color

2. What is the importance of meiosis and fertilization in sexual reproduction?

Molecules are the smallest units of matter with the characteristic properties of a substance. a. True b. False

For the following hypothetical reaction: 3A + 2B - > 3C. How many moles of C can you produce with 5 moles of A and excess B?

Which of the following statements is true of enzymes? A. they change shape after a reaction B. They don't provide an active site for substrates to bind in a reaction C. They're unusable after a reaction D.