2. Identify the following as human (H) or nonhuman (N) possible sources of error:

a. The balance used has not calibrated since it was originally plugged in___

b. Not putting the final answers in their correct number of significant figures___

c. Just as you were recording the temperature of a solution, the room suddenly feels cooler___

d. The electronic scale you use reads 0.05 g too high for all your mass measurements___

The diagram shows the positions of the sun, moon and earth during spring tides, when the high tides are at their highest and low tides at their lowest. what is it about these positions that causes these high and low tides?

Express the following number in scientific notation. 0.026890 =

Why is the bond angle in a water molecule less than the bond angle of methane? a. the central oxygen atom in water has two lone pairs of electrons, whereas the central carbon atom in methane has no lone pairs. b. the central hydrogen atom in water has one lone pair of electrons, whereas the central carbon atom in methane has two lone pairs. c. the central oxygen atom in water has four lone pairs of electrons, whereas the central carbon atom in methane has only one lone pair. d. the central oxygen atom exerts more repulsive force on surrounding atoms than the central carbon atom in methane does. reset next