One molecule of the oxide of element z reacts with six molecules of water to
produce an acidic compound. what is element z ?

What conclusion can you draw from this experiment about the components of the black ink?

According to the passage, which of these is true about gray water systems? a) gray water systems use plants that require less water. eliminate b) gray water systems require the use of less fossil fuels. c) gray water systems reduce the amount of fresh water used. d) gray water systems reduce the amount water used by shower heads.

Of the following elements, which is the least reactive? a. c b. h c. li d. he