What is the percent composition of hydrogen in a compound if the mass of the initial compound is 276 grams and the mass of collected hydrogen after decomposition is 41.4 grams?

A.

6.6%

B.

10.0%

C.

15.0%

D.

21.2%

Which of the following elements is less reactive than the others? Bromine (Br) Oxygen (O) Selenium (Se) Sulfur (S)

An alkyne C-H bond absorbs at higher wave number than an alkene C-H bond. What does this tell you about the strength of these two bonds? Multiple Choice The alkyne C-C bond is stronger. The alkene C-C bond is stronger.

Generally, as you go from left to right on the periodic table, what happens to: A) Atomic radius? B) First ionization energy? C) Electronegativity?

You have a gas stored in a rigid container (fixed volume). Explain the relationship between a decrease in temperature, collisions, and kinetic energy within the container.

Large pool of blood is found in the center of a room with a tile floor. There are zigzagging, arc-like bloodstains on one wall with drops of blood 1-4 mm in size and drips running down the wall.

What river basin provide river water to charolette and gastoia?

8. Calculate the molar mass of an alkane with the mole- cular formula C H18.

What is DNA? What information does it carry? Where is DNA located?

5. Differences in which property allow the separation of a sample of sand and seawater by filtration? A) concentration of ions B) volume of sample C) mass of sample D) particle size

Describe the reaction of a weak acid and a strong base. In general, what will the final pH be when the reaction between equal moles of a weak acid and a strong base is complete?