Which of the following describes the difference between nitrogen-14 and nitrogen-15?
a. nitrogen-14 has 14 electrons, 14 protons, and 14 neutrons; nitrogen-15 has 15 electrons, 15 protons, and 15 neutrons.
b. nitrogen-14 has 7 electrons, 7 protons, and 7 neutrons; nitrogen-15 has 8 electrons, 8 protons, and 8 neutrons.
c. nitrogen-14 has 14 electrons, 14 protons, and 14 neutrons; nitrogen-15 has 14 electrons, 14 protons, and 15 neutrons.
d. nitrogen-14 has 7 electrons, 7 protons, 7 neutrons; nitrogen-15 has 7 electrons, 7 protons, and 8 neutrons.

Explain which group an element with the electron configuration 1s2 2s2 2p6 3s2 3p6 3d1 4s2 belongs to.

What are transitions between a liquid and a solid called? identify which way they are transitioning

7. using your knowledge of colligative properties explain whether sodium chloride or calcium chloride would be a more effective substance to melt the ice on a slick sidewalk. use 3 – 4 sentences in your explanation. 8. when a 2.5 mol of sugar (c12h22o11) are added to a certain amount of water the boiling point is raised by 1 celsius degree. if 2.5 mol of aluminum nitrate is added to the same amount of water, by how much will the boiling point be changed? show all calculations leading to your answer or use 3 – 4 sentences to explain your answer. 9. if 5.40 kcal of heat is added to 1.00 kg of water at 100⁰c, how much steam at 100⁰c is produced? show all calculations leading to an answer. 10. the freezing of water at 0⁰c can be represented as follows: h2o (l) ↔ h2o(s) the density of liquid water is 1.00 g/cm3. the density of ice is 0.92 g/cm3. in 3 – 4 sentences explain why applying pressure causes ice to melt.