Two students each measured the density of a quartz sample three times: Student A
Student B
1. 3.20 grams/mL 2.82 grams/mL
2.2.58 grams/mL 2.48 grams/mL
3. 2.10 grams/mL
2.59 grams/mL
mean 2.63 grams/mL
2.63 grams/mL
The density found in the Handbook of Chemistry and Physics for quartz is 2.65
grams/mL
(a) Which student measured density with the greatest precision? Explain your answer.
(b) Which student measured density with the greatest accuracy? Explain your answer.
Show calculation setups and answers for the following problems

On the periodic table, elements are arranged by which of the following. a. mass numbers. b. increasing atomic number. c. alphabetical order. or d. density

What is the typical rotational frequency frot for a molecule like n2 at room temperature (25∘c)? assume that d for this molecule is 1å=10−10m. take the total mass of an n2 molecule to be mn2=4.65×10−26kg. you will need to account for rotations around two axes (not just one) to find the correct frequency. express frot numerically in hertz, to three significant figures.

The image compares the arrangement of electrons in two different neutral atoms. a figure labeled atom q has a shaded sphere at the center of three concentric circles. the innermost circle has two black spheres. the middle circle has six black spheres. to the left of this figure is another figure labeled atom p. atom p has a shaded sphere at the center of three concentric circles. the innermost circle has two black spheres. the middle circle has seven black spheres. which of the following best explains the position of the two atoms in the periodic table?