Elements are placed in the same column of the periodic table because they share the same number of valance electrons.

a. True

b. False

What type of forces must the polar water molecules break to dissolve ethanol, C2H5OH? A) metallic B) covalent bonding C) hydrogen bonding D) electrostatic attraction

Which of the following statements does not accurately describe Precambrian Earth? A. The atmosphere was similar to that of early Mars and Venus. B. The oceans were chemically different from modern oceans. C.

You dip a piece of blue litmus paper in a solution of NaOH. What happens to the color of the litmus paper?

When jack climbed the bean stalk what did he see

100 g of 20% salt solution is mixed with 200g of 10% salt solution. Find out the concentration of the resulting solution.

What product (s) forms at the cathode in the electrolysis of an aqueous solution of k2so4?

What element is used as a shield to protect people from radioactive substances?

The frequency of a given region of the electromagnetic spectrum is more than 3 x 1019 HZ. Note that the speed of light is 2.998 x 108 m/s. Which waves are found in this region? A. gamma rays B. visible light C. microwaves D. radio waves E. x-rays

A farmer uses water to irrigate his potato crops. Which roles of water does this examplify

How was helium first discovered?